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now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what is a frictional force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and we 'll cover that in much more detail . but the simple answer is , unbalanced force on a body will always impact its velocity . it could be its speed , its direction , or both , but it does n't have to be both .
could someone pls explain the difference between inertial and non-inertial frames of reference in simple words with a simple example ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and the key word right over here is `` speed . '' if i had written `` impact the object 's velocity , '' then this would be a true statement . an unbalanced force on a body will always impact the object 's velocity .
so is the statement actually true for velocity ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and the key word right over here is `` speed . '' if i had written `` impact the object 's velocity , '' then this would be a true statement . an unbalanced force on a body will always impact the object 's velocity .
would the object be crushed ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
now this is after its traveled a little bit -- its new velocity vector might look something like this . and it 's traveling at the exact right speed so that the force of gravity is always at a right angle to its actual trajectory . it 's the exact right speed so it does n't go off into deep space and so it does n't plu...
the explanation of orbits ( from statement # 2 ) confused me : if you are always applying the force of gravity to a moon at a right angle to its current vector ( towards its planet ) , would n't the speed be forever increasing ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
that is what 's slowing it down . so in our everyday life , the reason why we do n't see these things go on and on forever is that we have these frictions , these air resistants , or the friction with actual surfaces . and then the last statement , `` an unbalanced force on an object will always change the object 's di...
does water have more friction than air ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i 'm inside of a pool or even if there 's absolutely no current in the pool , and if i were to try to push some type of object inside the water , it eventually comes to stop because of all of the resistance of the water itself . it 's providing an unbalanced force in a direction opposite it 's motion . that is what ...
what can be the examples of non-uniform motion ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
that would be true . but we wrote `` speed '' here . speed is the magnitude of velocity . it does not take into account the direction .
what 's the difference between velocity and speed ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i take an object , if i take my book and i try to slide it across the desk , the reason why it eventually comes to stop is because we have the unbalanced force of friction -- the grinding of the surface of the book with the grinding of the table . if i 'm inside of a pool or even if there 's absolutely no current in...
- does the 'resistance of the water ' mean viscous drag ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what is the difference between balanced and unbalanced force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
how is friction an unbalanced force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
but we wrote `` speed '' here . speed is the magnitude of velocity . it does not take into account the direction . and to see why this second statement is false , you could think about a couple of things .
what does speed is the magnitude of velocity , it does not take in account the direction mean ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i apply it in that same direction , i 'm just going to accelerate it in that same direction . so i wo n't necessarily change it . even if i were to act against it , i might decelerate it , but i wo n't necessarily change its direction .
wo n't the speed also be impacted if there is a change in direction ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so the force , the inward force , the tension from the rope pulling on the skater in this situation , would have only changed the skater 's direction . so and unbalanced force does n't necessarily have to impact the object 's speed . it often does .
say the change is upwards , meaning the object starts moving vertically upwards due to the unbalanced force , wo n't gravity have a part in the reduction of speed ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so i 'll let you think about that . so let 's think about these statement by statement . so our first statement right over here , `` if the net force on a body is zero , its velocity will not change . ''
why the first statement is true ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
this is absolutely true . and this is the example we gave . if i take an object , if i take my book and i try to slide it across the desk , the reason why it eventually comes to stop is because we have the unbalanced force of friction -- the grinding of the surface of the book with the grinding of the table .
when sal gave the example for concept 3 , if there was no friction or any resistance so the concept would have failed ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
statement number two , `` an unbalanced force on a body will always impact the object 's speed . '' also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . ''
also , how does statement # 1 restate the n1l ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
does the frictional force act in a vacuum ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . '' and statement four , `` an unbalanced force on an object will always change the object 's direction . '' so i 'll let...
can a moving object come to rest on its own , well after a really long time , but without being treated by unbalanced forces ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so if that is some type of planet , and this is one of the planet 's moons right over here , the reason why it stays in orbit is because the pull of gravity keeps making the object change its direction , but not its speed . its speed is the exact right speed . so this was its speed right here .
my question is : how the speed of moon remains the same ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i apply it in that same direction , i 'm just going to accelerate it in that same direction . so i wo n't necessarily change it . even if i were to act against it , i might decelerate it , but i wo n't necessarily change its direction .
why does n't speed of the revolving moon change ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so if that is some type of planet , and this is one of the planet 's moons right over here , the reason why it stays in orbit is because the pull of gravity keeps making the object change its direction , but not its speed . its speed is the exact right speed . so this was its speed right here .
what is the exact difference between speed and velocity ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so i 'll let you think about that . so let 's think about these statement by statement . so our first statement right over here , `` if the net force on a body is zero , its velocity will not change . ''
for statement # 1 can the statement be false if frictional force is present ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
there will always be some minuscule ones , but we 'll assume no gravitational interactions . absolutely no particles that it 's bumping into , absolute vacuum of space . this thing will travel on forever .
sal says the is a minuscule amount of gravity in space , what causes gravity in space ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . '' and statement four , `` an unbalanced force on an object will always change the object 's direction . ''
if a person on a moving vehicle throws a ball vertically upwards it comes back to his hands after a short interval of time , how is it possible ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting .
how is it possible that when the `` net force '' is zero , the velocity would not change ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so let 's think about these statement by statement . so our first statement right over here , `` if the net force on a body is zero , its velocity will not change . '' this is absolutely true .
the example shown is when the net force is nonzero , right ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . '' and statement four , `` an unbalanced force on an object will always change the object 's direction . ''
what is the difference between balanced and unbalanced forces ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
this is absolutely true . this is actually even another way of rephrasing newton 's first law . if i have some type of object that 's just traveling through space with some velocity -- so it has some speed going in some direction , and maybe it 's deep space .
can the example ''a book on a table '' be of 1st law and 3rd law of newton both ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so if that is some type of planet , and this is one of the planet 's moons right over here , the reason why it stays in orbit is because the pull of gravity keeps making the object change its direction , but not its speed . its speed is the exact right speed . so this was its speed right here .
what is the speed of light ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what are external force that cause firecracker explode ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so if that is some type of planet , and this is one of the planet 's moons right over here , the reason why it stays in orbit is because the pull of gravity keeps making the object change its direction , but not its speed . its speed is the exact right speed . so this was its speed right here .
when its propulsion engine is shut down , does it continues to gain speed for a short time , then slows down , and eventually stop ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true .
what is the difference between weight and mass ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
well , the skater is going to travel . their direction is actually going to change . and they could hold on to the rope , and as long as they hold on to the rope , they 'll keep going in circles .
what do actually mean by latent heat of vaporisation ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
that would be true . but we wrote `` speed '' here . speed is the magnitude of velocity . it does not take into account the direction .
what is the difference between speed and velocity ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
statement number two , `` an unbalanced force on a body will always impact the object 's speed . '' also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . ''
for statement # 3 , does light also apply ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
but we wrote `` speed '' here . speed is the magnitude of velocity . it does not take into account the direction .
what is the exact meaning of magnitude ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
that would be true . but we wrote `` speed '' here . speed is the magnitude of velocity . it does not take into account the direction .
what is the difference between speed and velocity ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if the planet was n't there , it would just keep going on in that direction forever and forever . but the planet right over here , there 's an inward force of gravity . and we 'll talk more about the force of gravity in the future . but this inward force of gravity is going to accelerate this object inwards while it tr...
what about gravity acting upon matter on the surface of the earth , does it alter the net force applied to the object ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
2 ) what does unbalanced force mean ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so the force , the inward force , the tension from the rope pulling on the skater in this situation , would have only changed the skater 's direction . so and unbalanced force does n't necessarily have to impact the object 's speed . it often does .
what is the force needed to maintain an object at constant speed in a straight line in outer space [ far from all outside influences ] is equal to ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so this is not true . an unbalanced force on an object will not always change the object 's direction . it can , like these circumstances , but not always .
just wondering , would air be an unbalanced force if you were pushing an object ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
statement number two , `` an unbalanced force on a body will always impact the object 's speed . '' also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . ''
: ) also in the video when sal states that the 2nd statement is false due to the word speed- why , though ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so the force , the inward force , the tension from the rope pulling on the skater in this situation , would have only changed the skater 's direction . so and unbalanced force does n't necessarily have to impact the object 's speed . it often does .
so does n't that imply that a force can be seen a `` balanced '' or `` unbalanced '' depending on the context ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i had written `` impact the object 's velocity , '' then this would be a true statement . an unbalanced force on a body will always impact the object 's velocity . that would be true .
so friction could be seen as a `` balanced '' force in reference to the velocity of the object '' , but if the object 's velocity is removed from the equation , then friction is seen as `` unbalanced '' ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and to see why this second statement is false , you could think about a couple of things . and we 'll do more videos on the intuition of centripetal acceleration and centripetal forces , inward forces , if this does not make complete intuitive sense to you just at this moment . but imagine we 're looking at an ice skat...
are there any other situations where unbalanced forces do not always effect speed besides centripetal acceleration ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i had written `` impact the object 's velocity , '' then this would be a true statement . an unbalanced force on a body will always impact the object 's velocity . that would be true .
does it always affect velocity except in centripetal acceleration ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
an unbalanced force on a body will always impact the object 's velocity . that would be true . but we wrote `` speed '' here .
for statement # 2 , the example in which you mention the skater and the rope , would it be true to say that his velocity would decrease as he is travel in the upward direction due to the downward acceleration of gravity acting against the motion ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and the key word right over here is `` speed . '' if i had written `` impact the object 's velocity , '' then this would be a true statement . an unbalanced force on a body will always impact the object 's velocity . that would be true . but we wrote `` speed '' here .
regarding the second statement , it is said that if the word speed was replaced by velocity , the statement would be true.but cant an unbalanced force also change the dimensions of an object without affecting its velocity ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what does an unbalanced force mean ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i apply it in that same direction , i 'm just going to accelerate it in that same direction . so i wo n't necessarily change it . even if i were to act against it , i might decelerate it , but i wo n't necessarily change its direction .
but do n't all bodies in the universe experience some type of gravitatioanl pull ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so this is not true . an unbalanced force on an object will not always change the object 's direction . it can , like these circumstances , but not always .
and the moon orbits ( goes around an object in circles ) moves because the other parts are pulling on the moon , and the parts that where holding on the moon lose energy ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if the planet was n't there , it would just keep going on in that direction forever and forever . but the planet right over here , there 's an inward force of gravity . and we 'll talk more about the force of gravity in the future .
if we thow a ball it is the force of gravity there so net forceon ball is not balanced so it increases its vel ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
is there a way to calculate what will be the magnitude of the force of friction for different objects moving on the same plane ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . '' and statement four , `` an unbalanced force on an object will always change the object 's direction . ''
if both the objects are pushed on the same table with forces such that the accelerations of the pencil box and the book starting from rest are equal , will the magnitude of friction acting on both the objects be equal ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if i had written `` impact the object 's velocity , '' then this would be a true statement . an unbalanced force on a body will always impact the object 's velocity . that would be true .
then an unbalanced force on a body will always impact the object 's velocity , right ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
but this inward force of gravity is going to accelerate this object inwards while it travels . and so after some period of time , this object 's velocity vector -- if you add the previous velocity with how much it 's changed its new velocity vector . now this is after its traveled a little bit -- its new velocity vecto...
why is the recoil velocity of a gun that has been fired much less than the velocity of the bullet that has left itd barrel ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so if that is some type of planet , and this is one of the planet 's moons right over here , the reason why it stays in orbit is because the pull of gravity keeps making the object change its direction , but not its speed . its speed is the exact right speed . so this was its speed right here .
would n't friction reduce its speed and eventually make it crash into the planet ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
is a vector basically the direction of a force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
that would be true . but we wrote `` speed '' here . speed is the magnitude of velocity . it does not take into account the direction .
what are those and how do they explain the difference between speed and velocity ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
this is absolutely true . this is actually even another way of rephrasing newton 's first law . if i have some type of object that 's just traveling through space with some velocity -- so it has some speed going in some direction , and maybe it 's deep space .
if there is an acceleration ( in the motion of an object ) , it means newton 's first law can not be aplied , right ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so the force , the inward force , the tension from the rope pulling on the skater in this situation , would have only changed the skater 's direction . so and unbalanced force does n't necessarily have to impact the object 's speed . it often does .
if i push an item across the floor , will my applied force effect the speed of the object ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so this is not true . an unbalanced force on an object will not always change the object 's direction . it can , like these circumstances , but not always .
in the first question if we rotate an object that is we put it in circular motion by applying a constant force then wo n't its velocity change as direction keeps changing ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so this is not true . an unbalanced force on an object will not always change the object 's direction . it can , like these circumstances , but not always .
if an unstoppable force came to an un movable object what would happen ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
this is absolutely true . this is actually even another way of rephrasing newton 's first law . if i have some type of object that 's just traveling through space with some velocity -- so it has some speed going in some direction , and maybe it 's deep space .
2.31 minutes are subatomic particles in black holes subject to newton laws of motion ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so the force , the inward force , the tension from the rope pulling on the skater in this situation , would have only changed the skater 's direction . so and unbalanced force does n't necessarily have to impact the object 's speed . it often does .
for statement # 2 , if there is an unbalanced force , does n't it mean that the object will be accelerating and therefore changing its speed ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting .
how do you figure out net force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
if the planet was n't there , it would just keep going on in that direction forever and forever . but the planet right over here , there 's an inward force of gravity . and we 'll talk more about the force of gravity in the future .
in 4.01 ... sal says about polar gravity now what is it that ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what does a unbalanced force mean ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so if that is some type of planet , and this is one of the planet 's moons right over here , the reason why it stays in orbit is because the pull of gravity keeps making the object change its direction , but not its speed . its speed is the exact right speed . so this was its speed right here .
will centrifugal force not affect the speed ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true .
what are the precise definitions of those terms ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what is an unbalanced force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so i 'll let you think about that . so let 's think about these statement by statement . so our first statement right over here , `` if the net force on a body is zero , its velocity will not change . ''
in the statement 3 , does gravity act along with the frictional force or it is just the friction ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
also an interesting statement . statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . '' and statement four , `` an unbalanced force on an object will always change the object 's direction . ''
objects tend to stay moving because of a force called ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting .
in the first statement , how can the net force be zero ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so i 'll let you think about that . so let 's think about these statement by statement . so our first statement right over here , `` if the net force on a body is zero , its velocity will not change . ''
how do you explain what 's happening in the third statement in physics terms ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and to see why this second statement is false , you could think about a couple of things . and we 'll do more videos on the intuition of centripetal acceleration and centripetal forces , inward forces , if this does not make complete intuitive sense to you just at this moment . but imagine we 're looking at an ice skat...
do we need an integral to determine the balance of forces at some later time before it comes to a stop ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so the force , the inward force , the tension from the rope pulling on the skater in this situation , would have only changed the skater 's direction . so and unbalanced force does n't necessarily have to impact the object 's speed . it often does .
so are there chances for an unbalanced force to impact an object 's speed ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
statement number two , `` an unbalanced force on a body will always impact the object 's speed . '' and the key word right over here is `` speed . '' if i had written `` impact the object 's velocity , '' then this would be a true statement .
is n't the key word for the second last statements supposed to be the word `` always '' ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what is an unbalanced force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
an unbalanced force on an object will not always change the object 's direction . it can , like these circumstances , but not always . so `` always '' is what makes this very , very , very wrong .
for the concepts above does nuclear particles like photons , mesons & gluons apply with other things like electromagnetic radiation and other waves ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so this is not true . an unbalanced force on an object will not always change the object 's direction . it can , like these circumstances , but not always .
but if that object went on in space would'nt the object be pulled in by the gravity of the planet ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true .
explain how to use the graphs to determine relationships ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
but this inward force of gravity is going to accelerate this object inwards while it travels . and so after some period of time , this object 's velocity vector -- if you add the previous velocity with how much it 's changed its new velocity vector . now this is after its traveled a little bit -- its new velocity vecto...
so , how is it possible for an object to maintain a velocity even when it has weight ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
so this is not true . an unbalanced force on an object will not always change the object 's direction . it can , like these circumstances , but not always .
would n't the object always have an object acting on it ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting .
first law of the kepler doing all the planets that orbit is elliptical , according to the magnitude of force in this case does not change ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
this is absolutely true . this is actually even another way of rephrasing newton 's first law . if i have some type of object that 's just traveling through space with some velocity -- so it has some speed going in some direction , and maybe it 's deep space .
what is the law of conservation of momentum and the law of universal gravitation ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what is the unbalanced force here ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
let 's say i have a block right over here , and it 's traveling with some velocity in that direction -- five meters per second . if i apply an unbalanced force in that same direction -- so that 's my force right over there . if i apply it in that same direction , i 'm just going to accelerate it in that same direction ...
what is the external force ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true .
what is the measure for inertia ?
now that we know a little bit about newton 's first law , let 's give ourselves a little quiz . and what i want you to do is figure out which of these statements are actually true . and our first statement is , `` if the net force on a body is zero , its velocity will not change . '' interesting . statement number two ...
statement number three , `` the reason why initially moving objects tend to come to rest in our everyday life is because they are being acted on by unbalanced forces . '' and statement four , `` an unbalanced force on an object will always change the object 's direction . '' so i 'll let you think about that .
so from statement 2 and 4 we get to know that -unbalanced force will always change the velocity of an object , it might be its speed , direction or both being altered under its influence , right ?
- have you ever wondered how you learned to interact with people ? well , it is through a process called socialization , and socialization is a life-long process where we learn about social expectations and how to interact with others . so everything we consider to be normal is actually learned through socialization . ...
so this example shows us how kids are raised , and really how they 're raised affects how they interact with others , and in this case , authority . so the wealthy kids were encouraged to challenge authority and to think independently , while the less wealthy kids were taught to submit to authority . schools are also a...
why when people of color challenge authority they more likely to be shot or maced vs when yuppies challenge authority ?
- have you ever wondered how you learned to interact with people ? well , it is through a process called socialization , and socialization is a life-long process where we learn about social expectations and how to interact with others . so everything we consider to be normal is actually learned through socialization . ...
so students do not just learn from their academic curriculum , but they learn social skills from interactions with teachers and other students . for example , we learn the importance of obeying authority , and that to be successful we must learn to be quiet , we must learn to wait , and to even act interested when we a...
perhaps , when the poor do act outside their stereotype then they are punished vs when yuppies act within their stereotype it 's ok ?
- have you ever wondered how you learned to interact with people ? well , it is through a process called socialization , and socialization is a life-long process where we learn about social expectations and how to interact with others . so everything we consider to be normal is actually learned through socialization . ...
so the less fortunate children were more likely to just accept what the doctor says without voicing their concerns at all . so this example shows us how kids are raised , and really how they 're raised affects how they interact with others , and in this case , authority . so the wealthy kids were encouraged to challeng...
`` obedience to authority ; waiting ; quiet '' are white skills ?
all right , let 's see if we can find the limit of 1 over the square root of 2 sine of theta over cosine of 2 theta , as theta approaches negative pi over 4 . and like always , try to give it a shot before we go through it together . well , one take on it is well , let 's just , let 's just say that this is going to b...
so let me algebraically manipulate this a little bit . so if i have 1 plus the square root of 2 , sine theta , over cosine 2 theta , as you can imagine , the things that might be useful here are our trig identities and in particular , cosine of 2 theta seems interesting . let me write some trig identities involving cos...
how does 1-2sin^2 ( theta ) get factored into squrt ( 2 ) sin ( theta ) ?
all right , let 's see if we can find the limit of 1 over the square root of 2 sine of theta over cosine of 2 theta , as theta approaches negative pi over 4 . and like always , try to give it a shot before we go through it together . well , one take on it is well , let 's just , let 's just say that this is going to b...
if we 're dealing with this over , you know , with this open interval , wait , actually , even disregarding that , theta , this theta , or this expression is continuous at , it is defined and it is continuous at theta is equal to negative pi over 4 so this is just going to be equal to 1 over 1 minus the square root of ...
how did sal know off the top of his head what sin ( ( -pi/4 ) ) was ?
all right , let 's see if we can find the limit of 1 over the square root of 2 sine of theta over cosine of 2 theta , as theta approaches negative pi over 4 . and like always , try to give it a shot before we go through it together . well , one take on it is well , let 's just , let 's just say that this is going to b...
well , all of these three are going to be differences of squares , so we can factor them in interesting ways , and remember , our goal at the end of the day is maybe cancel things out that are making us get this zero over zero , and if i could factor this into something that involved a 1 plus square root of 2 sine thet...
how is cos2 ( theta ) = cos^2 ( theta ) -sin^2 ( theta ) what is the difference between cos2 and cos^2 ?
all right , let 's see if we can find the limit of 1 over the square root of 2 sine of theta over cosine of 2 theta , as theta approaches negative pi over 4 . and like always , try to give it a shot before we go through it together . well , one take on it is well , let 's just , let 's just say that this is going to b...
so if i have 1 plus the square root of 2 , sine theta , over cosine 2 theta , as you can imagine , the things that might be useful here are our trig identities and in particular , cosine of 2 theta seems interesting . let me write some trig identities involving cosine of 2 theta . i 'll write it over here .
should you memorize all the double angle identities ?
all right , let 's see if we can find the limit of 1 over the square root of 2 sine of theta over cosine of 2 theta , as theta approaches negative pi over 4 . and like always , try to give it a shot before we go through it together . well , one take on it is well , let 's just , let 's just say that this is going to b...
so let me algebraically manipulate this a little bit . so if i have 1 plus the square root of 2 , sine theta , over cosine 2 theta , as you can imagine , the things that might be useful here are our trig identities and in particular , cosine of 2 theta seems interesting . let me write some trig identities involving cos...
how did sal go from cos ( 2*theta ) to cos^2 ( theta ) - sin^2 ( theta ) ?
all right , let 's see if we can find the limit of 1 over the square root of 2 sine of theta over cosine of 2 theta , as theta approaches negative pi over 4 . and like always , try to give it a shot before we go through it together . well , one take on it is well , let 's just , let 's just say that this is going to b...
all right , let 's see if we can find the limit of 1 over the square root of 2 sine of theta over cosine of 2 theta , as theta approaches negative pi over 4 . and like always , try to give it a shot before we go through it together .
this is probably pretty dumb , but someone please let me know if i 'm getting this right ... mr. khan is saying that the whole entire point that we are doing this is to see what the y value , or f ( x ) , would be if the original equation was continuous at theta=-pi/4 ?