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le in one direction and under the needle in the opposite In this way the magnetic direction. effect of the current is magnified and the compass-needle will be deflected. By Left-Hand applying (Sec. V:48), the direction of current may be determined. By noting the amount of deflection of the needle a rough com- Rule the ... |
(Sec. V:49), indicates that the loop, when carrying current, will have an N-pole and an S-pole. Following the Law of Magnetism (Sec. V:2), the N-pole of the loop will be attracted to the S-pole of the permanent magnet while the S-pole of the loop will face the N-pole of the magnet. V:53 THE D'ARSONVAL GALVANOMETER Fig... |
. Such a conductor cannot carry a large current without undue (Sec. V:71), and consequent heating melting of the wire. The movable coil of such an instrument is rarely allowed to carry more than 0.05 amperes. If the ammeter is to be used to mea- Fig. 27:19 Ammeter Connected in Series. 311 ) Chap. 27 MAGNETISM AND ELECT... |
a voltmeter must have a very high resistance to avoid parallel with drawing a large current. As a result the total current in the circuit will not be affected significantly. A galvanometer may be converted to a voltmeter by the addition of a high resistance in series with the moving coil (Fig. 27:20). Example A galvan... |
armature turns is usually provided by an Fig. 27:24 Electric Motor. The Commutator Reverses the Direction of Electron Flow Every 180°. electromagnet, since such a magnet may be made more powerful than a permanIts windings are called the ent type. field coils to difTerentiate them from the armature coil. The field coil... |
direction of the current and the polarity of the solenoids. 315 Chap. 27 MAGNETISM AND ELECTRICITY 3. (a) Why is soft iron, rather than steel, used as the core in most electromagnets? (b) How may the strength electromagnet be increased? of an 8. (d) How may a galvanometer be (i) an modified to convert it into ammeter ... |
very ordinary education, became an apprentice to a book- of pressed the great chemist. Sir Humphrey Davy, so much that at the age of twentyone he became his assistant at the Royal Institution. Within twelve years he was made a director of the Institution. From the time that Oersted demonstrated the magnetic effect of ... |
the magnet remains stationary in the solenoid, i.e., while the strength of the magnetic field remains constant. When the magnet is withdrawn quickly from the solenoid, the strength of the magnetic field decreases, and the galvanometer needle is again deflected, but this time in the opposite direction. It is apparent, ... |
found that a stronger induced current flows in the coil having the larger number of turns. Therefore, it is evident that the E.M.F. induced in a circuit is proportional to the number of turns of the conductor cut by the varying magnetic field. N-pole at the end of the solenoid where the magnet enters. This N-pole repe... |
�break”) and in the opposite direction when it the “make”). The idea of opposing mag- primary is closed. closed that the (at It is 319 Chap. 28 MAGNETISM AND ELECTRICITY As it nears the position at right angles to the first, much cutting of the lines of force netic fields is carried out here in that the induced current... |
to overcome the opposition of the fields of force is transformed into electrical energy. While the earth inductor itself is of no practical value it does permit a preliminary study of the generation of electricity by induction. This simple knowledge has made possible the development of all the many forms of electric g... |
in position (9). Thus, during one complete rotation of the coil, the induced current starts at zero, increases to a maximum, falls to zero, increases to a maximum in the opposite direction, and again falls These (7), decreases in zero. to changes are summarized in Fig. 28:7. A current with such characteristics is said... |
are so placed that they rest on the insulating material between the bars at the instant when the elec- V : 64 TRANSFORMERS Transformers are used to change the voltage in an A.C. circuit as required. A transformer consists of two separate coils of insulated wire, the primary and secondary coils, wound on the same soft ... |
voltage Number of turns on primary coil 6 X 120 2000 6.•.x=r—X 2000 =100.’. there should be 100 turns on the secondary coil. 324 ELECTROMAGNETIC INDUCTION Sec. V:65 V:65 THE TELEPHONE The first telephone was invented by Alexander Graham Bell, a Scottish emigrant to the United States, 1875, and first used between Brant... |
only weak signals This is because of the will be heard. very small changes in resistance in the carbon granules of the transmitter as compared to the total resistance of the circuit. The slight variations in current do not cause enough variation in the receiver electromagnet to give satisfactory reception. To overcome... |
, as both consist of primary and secondary coils of different numbers of turns of wire wound about a common soft iron core. Whereas the transformer can utilize the changing magnetic field caused by alternating current to step up the voltage, the same operation is impossible with a direct current for lack of changing ma... |
actual practice the weaker of the two is practically eliminated by the use of a condenser. Induction coils can be used for operalthough modern ating X-ray tubes, tubes are mainly transformer operated. They are also employed in some forms of laboratory research where moderately high voltages are required, and in the ig... |
across contact points the time. 3. 4. ELECTROMAGNETIC INDUCTION Sec. V: 69 arcing (and consequent damage to the points) and to ensure a rapid break as In described in the previous section. order to withstand the high voltages (of the order of 10,000 volts), the leads from the secondary coil to the distributor and spar... |
(a) completed (b) broken? Describe a simple induction coil as to (a) purpose (b) structure (c) action (d) uses. 329 Chap. 28 MAGNETISM AND ELECTRICITY B 1. A transformer is required to provide 6 volts to operate an electric door-bell on a 120 volt circuit. If the primary coil has 1 600 turns, how many turns should be ... |
resources. The energy of falling water has been turn the huge turbines harnessed which rotate the armatures of large genSteam-generating erators plants have become common in which (Fig. 29:1). to the energy from coal is utilized. In recent years heat from an atomic pile is These being used in the same way. latter meth... |
A. Edison of Canada Ltd. Fig. 29:3 The Incandescent Lamp. 334 ELECTRICAL ENERGY Sec. V:74 \ \ \'resistance wire. This is an alloy of nickel (80%) and copper (20%) which can be heated to a high temperature without melting, and oxidizing very slowly even when red hot. In addition, it has a resistance of about sixty time... |
electric arc is also applied in electric ships’ plates, Boiler welding. plates, etc., can be welded by connecting the plates to the negative of a D.C. supply, applying the positive side to the weldingrod where the weld is to be made. V:75 BUYING ELECTRICAL ENERGY Since electricity is able to do work, it is a form of e... |
. voltage is 2. (a) What is the function of a fuse in an electric circuit? (b) Describe the structure and action of a simple fuse. 3. (a) Make a labelled diagram of an electric-light bulb. (b) Explain the function of each part labelled in (a). 4. List three appliances found in each of the following, in which the heatin... |
110 volt circuit. The electricity costs 3.5 cents per kilowatt-hour. 10. What is the cost to a storekeeper of leaving a 40 watt light bulb burning near his safe for 36 hours if electricity costs 3 cents per kilowatt-hour? 11. An electric stove element draws 5 amperes on the 220 volt circuit. is turned on for 4 hours, ... |
in appearance with the even degree of though the tube is evacuated as com- evacuation, continues inside pletely as possible. The current flows through the gas at reduced pressure because the gas becomes ionized. The electrons expelled from the atoms of gas are attracted to the anode where they re-enter the metallic pa... |
light and dark patches known as striations. The Faraday dark space increases in size at this low pressure, and the cathode glow moves away from the cathode, leaving a dark space between it and the cathode called the Crookes’ dark space (Fig. 30:2). When the pressure is about 0.1 mm. the positive column disappears alto... |
RAYS While experimenting with discharge tubes at very low pressure, Roentgen, in Germany, in a fluorescent screen some distance away glowed brightly even when the discharge tube was covered with black paper, and 1895, noted that A Chest X-Ray Machine. General Electric 342 ELECTRONICS Sec. V:79 objects placed between th... |
metal castings, and research scientists find them a useful aid in many of their investigations. V : 80 THE ELECTRONIC TUBE Just as a tap acts as a valve to control the flow of water through the pipes of a house, so the electronic tube acts as a valve to control the flow of electrons in an electric circuit (Chap. 31, E... |
30 MAGNETISM AND ELECTRICITY flow. current Thus the cathode will be repelled and no current passes will through the tube in one direction only, from cathode to anode, and a direct current flows in the plate circuit. The tube has been used to obtain direct current from an alternating-current supply. Such a process is c... |
set free by light. Students Positively Charged Anode Serves as Plate to Attract Emitted Electrons Light-Sensitive Cathode Gives Off Electrons when Light Hits It Electrons Escape from Surface Electric Bell Fig, 30:12 Photoelectric Cell. burglar alarms, control dangerous machinery, reproduce sound for movies, count arti... |
non-magnetic substances. (Ref. Sec. V:2) Apparatus Bar magnet, assortment of small articles made from iron, paper, glass, wood, copper, nickel, rubber, tin, silver, plastic, etc. Method Approach each of the articles in turn with the bar magnet. Tabulate your results. Observations State which objects were attracted and... |
2. MAGNETISM AND ELECTRICITY Why do we call one end of a bar magnet the north-seeking pole and the other end the south-seeking pole? What abbreviations for these are in common use? EXPERIMENT 4 To investigate the effect of bringing like and unlike magnetic poles together, (Ref. Sec. V:2) Apparatus Two bar magnets of k... |
. Repeat part 2 with an N-pole and an S-pole about 2 in. apart. Observations 1. Where are the lines of filings most concentrated? 2. Where are the lines least concentrated? 3. What is the general shape of the lines formed? 4. Do any of the lines appear to cross each other? 5. Where do the lines seem to begin and end in... |
the nail, how was the N-pole of the compass-needle affected? 5. What occurred when the S-pole of the magnet was used? Conclusions 1. Why did the nail act as a magnet when under the influence of the bar magnet? 2. Why did it not remain a magnet when the bar magnet was removed? 3. What polarity was induced in the end of... |
rest. 3. Insert the iron sheet between the compass-needle and the magnet and repeat the above procedures, taking care that all other conditions remain the same as before. 4. Repeat part 3 using other materials. 355 Chap. 31 MAGNETISM AND ELECTRICITY Observations 1. Number of v.p.s. without shield 2. Time to come to fu... |
the polarity of each piece. Observations By means of diagrams illustrate your observations. Conclusion From these observations what inference can be made about the basic structure of a magnet? EXPERIMENT 11 To investigate further experimental evidence for the theory of magnetism. (Ref. Sec. V:7) Apparatus Test-tube, i... |
electrical charges and to establish the law of electrical charges. (Ref. Sec. V:11) Apparatus Two ebonite rods, two glass cat’s fur, silk. rods, insulated stand, thread, stirrup, Method 1. Charge an ebonite rod by rubbing it with cat’s fur. Suspend the charged rod in the stirrup attached by a thread to the insulated s... |
it touches. Withdraw the charged ebonite rod. 2. Approach but do not touch the knob of the charged electroscope with (a) another negatively charged rod (b) a positively charged glass rod (c) a stick of sealing-wax that has been rubbed with flannel. 3. Remove the charge from the electroscope by touching the knob with a... |
the rod. Again test each sphere as in part 2. 4. Touch the spheres to each other and test each for a charge as in part 2. 5. Repeat parts 3 and 4, using a positively charged rod. Observations State what was observed. Explanation Explain your observations in this experiment with reference to the electron theory. 361 9 ... |
-plane and electroscope again test them for charge. 4. Test the sphere for the presence of electric charge. Observations Describe clearly what occurred in the above steps. Explain fully. Conclusion Where do electric charges reside on a charged object? B. Using Conductors of Different Shapes 1. Using the disc of the ele... |
dichromate? 4. What eventually happens to the electrodes as the action continues? Explanations 1. What is the cause of the changes at the zinc plate? 2. What must have been produced to make the light bulb glow? 3. Account for the change in the glowing that is observed. 4. What is the action of the potassium dichromate... |
Name the units used for measuring potential difference, current strength, and resistance. 2. Define “ohm”. EXPERIMENT 23 To determine the resistance of an unknown resistance by the voltmeter-ammeter method. (Ref. Sec. V:38) Apparatus Voltmeter, ammeter, rheostat, dry cells, unknown resistance. Method 1. Connect the vo... |
cell almost to the top with electrolyte. Completely fill the two test-tubes with the same liquid and invert one over each electrode as shown in the diagram. Connect the electrodes to the current source noting which is the cathode ( — ), and which is the anode ( + ) 2. Allow the current to flow until one test-tube is a... |
and test it with a glowing splint. examine the deposit at the cathode. Also, Observations Describe all observations. Conclusion What is obtained at (a) the anode (b) the cathode? Explanation Write a brief e.xplanation of the electrolysis of copper sulphate solution. EXPERIMENT 27 To discover the factors that affect th... |
current flow gm. gm. gm. sec. Current strength (average of ammeter readings) = amp. Calculations 1. Determine the weight of copper deposited in 1 second. 370 EXPERIMENTS ON MAGNETISM AND ELECTRICITY 2. Knowing that the electrochemical equivalent of copper is 0.000329, calculate the current flowing in the circuit. Conc... |
full of sulphuric acid solution. Immerse the lead strips in the solution so that they do not touch each other, connect them in series with the dry cells and let the current flow for about 5 minutes. Momentarily insert the galvanometer into the circuit to determine the direction of the current. Note any changes observe... |
current. 2. State the Left-Hand Rule. Question Describe the magnetic field obtained if the above conductor were coiled into a single loop. EXPERIMENT 32 To investigate the magnetic field surrounding a helix carrying electric current, (Ref. Sec. V:49) Apparatus Dry cell, helix, iron-filings, magnetic compass, piece of ... |
Fig. 27:14) consists of several coils of wire with different numbers of turns, e.g., 1, 25, 100, in each coil. 1. Describe how this instrument may be used (a) to determine the to compare the strengths of different direction of a current (b) currents. 2. What is the purpose of the coils with different numbers of turns? ... |
armature through 180°. Note the changes in the position of the commutator segments and brushes as you do so. Again determine the polarity of the armature. Replace the magnets. 3. (a) Vary the current by changing the rheostat setting. (b) Vary the magnetic field by changing the distance of the poles from the ends of th... |
induced electromotive force (E.M.FJ. (Ref. Sec. V:59) Apparatus Same as for experiment 36, iron core to fit in hollow core of primary coil. Method 1. With the larger solenoid attached to the galvanometer, insert the bar magnet into the hollow core first slowly and then rapidly. Compare the strengths of the induced E.M... |
inserted S-pole withdrawn Conclusions 1. What effect does the magnetic field produced have on the motion that is inducing the current? 2. State Lenz’s Law. Questions 1. Make a series of diagrams to illustrate the above observations. Show the direction of motion of the magnet and the polarity produced. 2. Use Lenz’s La... |
in this experiment? 2. What modihcation in the structure of the apparatus would permit a reduction in the speed of rotation of the armature in question 1? 381 Chap. 31 MAGNETISM AND ELECTRICITY EXPERIMENT 40 To study self-inductance. (Ref. Sec. V:67) Apparatus Coil with many turns wound around a soft iron core, three ... |
stages of evacuation. Explanation Why does the discharge occur in the evacuated tube rather than between the discharge points? Conclusion What effect does reducing the pressure of a gas have on its electrical conductivity? Question. According to the electron theory, what constitutes the current of electricity (a) thro... |
Connect the circuit as shown in the diagram using the plate and filament voltages recommended for the tube available. 2. With Ki open (a) close Kz making the plate positive and watch the galvanometer for any deflection. (b) reverse the terminals of the ‘‘5” battery so the plate is negative and repeat part (a). 3. With... |
step above? Explanation Account for the observations. Conclusions What is meant by photo-emission of electrons? 386 MODERN DEVELOPMENTS IN PHYSICS This Electron Microscope Permits Viewing of Particles Smaller Than One 10-Millionth of an Inch in Any Diameter. It Provides Magnification 50 Times Greater Than Heretofore P... |
YSICS of the human eye produces the illusion of a continuous line of light on the screen. Thus, it is easy to see that if one voltage is used to make the beam sweep from side to side at a known uniform rate, another voltage applied to the ver- Illus. Courtesy of Canadian Marconi Co. A Picture Tube deal deflection plate... |
and, consequently, with the brightness of light from the scene. This return beam constitutes a weak current which is amplified, sent to a transmitter where it modulates ultra high frequency carrier waves that are broadcast much as are radio waves. The main part of the receiving aptube, paratus called a kinescope (Fig.... |
pass and where they become deflected. The arrangement of lenses is similar to that in the optical microscope but the object to be studied is very much thinner (1/100,- 395 ). Chap. 32 MAGNETISM AND ELECTRICITY ELECTRON MICROSCOPE OPTICAL MICROSCOPE ^SOURCE OF ILLUMINATION (Electrons) (Light) CONDENSER LENS (Magnetic) ... |
. The number of protons in the nucleus of the atom is the atomic number or nuclear charge. Since the atom is electrically neutral, the Fig. 32:12 Structure of Some Atoms. (MN = Mass Number; AN = Atomic Number) 398 MODERN DEVELOPMENTS IN PHYSICS Fig. 32:13 Isotopes of Hydrogen. Tritium MN = 3 AN = 1 number of electrons ... |
Tn of nuclear transformation, Nuclear Fission, in which the uranium nucleus was split into two nearly equal parts with the release of a large amount of energy (Fig. 32:15). Another interesting feature of the fission of uranium is that during the process further neutrons are emitted in relatively larger numbers than tho... |
million times as much energy as one atom of carbon or if you have equal masses of coal and uranium the amount of energy released from the uranium is 3 million times as great. There is little wonder, therefore, that the search for uranium goes on at a feverish pace. gives volts. that, coal It is if Atomic Fusion to In ... |
b) 1 2.3, 6,000,050.465 c.c. (c) 100 m. (i) 28.1 ft. (hi) 64.4 km. per hr. (ii) 22.5 cu. dm. (hi) 22.5 litres 225.000 dg., 22.5 kg.; (b) (i) 28.4 gm. (ii) 909. kg. (hi) 5.4 pints 102.70; (b) (ii) 0.35 (hi) 27 X 101; (j) (i) 14 x 102 (h) 0.50 (hi) 9.0 Chapter 3, Section I : 9—Page 22 30,000, 2.36, 60,005.44 sq. cm.; (c)... |
. per c.c. 18 (a) 19.5% (b) 13.4% 5 64. 10 0.068 11 0.59 15 0.80 14 0.8722 20 5.9 19 0.42 c.c. 23 0.9 gm. per c.c. 21 9.9 gm. per c.c. 22 8.7 gm. per c.c. Chapter 4, Section I : 15—Page 32 1 (b) (i) 100 gm. (ii) 790 gm. 3 (c) (i) 2.6 gm. (ii) 4.3 c.c B 5 (i) 7.14 (ii) 70 c.c 2 (a) 68 gm.; (b) 625.0 lb. 4 10.5 1 (a) 30 ... |
.7°C. 12 (a) 56.5 ft. 2.67,.67 sec. 4 (a) 320 v.p.s.; (b) 667 v.p.s. 3 (a) 1170 or 11.7 X 10^ ft. per sec.; 5 (a) 1.50 ft.; (b) 56.0 cm. 7 (a) 15°C.; 11 (a) 357 m.persec.; (b) 42°C. 14 750 m.p.h.’ 10 259 v.p.s. 13 22.6 sec. 8 5595 ft. 9 1.33 m. Chapter 7, Section II : 18—Page 71 6 (b) (i) 750 v.p.s., (ii) 100 v.p.s.; (... |
— Page 124 2 37.8, 176.7, —140, — 45.6°C. 3 (a) —40°; (b) 4 (a) (i) 330, 250° K. (ii) 25, -36° C.; (b) (i) 309.7, 255.2, °K. (ii) 212, B 1 59, 392, —76, — 459.4°F. 320° — 459.4°F. Chapter 14, Section III : 32—Page 160 2 1600, 8400 cal. (i) A (b) B 350. cal., (ii) 5328 B.T.U., (iii) 179.4 cal. 4 (b) 0.087. 7 4000, 9 (a)... |
6 52.8 X 1042 7 4 3 yg^rs. Chapter 17, Section IV : 20—Page 194 A. 5 (a) 7. 405 A 2 (c) dioptres. B I 1.20 B (i) 10 o’clock (ii) 5.45 o’clock (v) — 60 cm. 5 — 9.23 in. 11 — 4.5 in. 12— 8.6 cm. 1 oc 13 20 in. 14 2.2 in. Chapter 18, Section IV ; 34— Page 211 ANSWERS 4 (a) 6 3 ft. (i) 50 cm. (ii) 60 cm. (iii) 90 cm. (iv)... |
2 amp. (iii) 60, 48 volts; (d) (i) 13 B 2 212.5 or 21 X 10 volts 1 12 ohms 4 (a) 0.12 amp.; (b) 11.9 or 12 volts and 0.06 volts 5 (a) 22 ohms; (b) 5.5 ohms 6 (a) 41.3 ohms; (b) 0.333 amp.; (c) 2.66 amps. 7 (b) 6 volts; (c) 0.9 ohm 8 16.7 or 17 ohms. 9 (a) 3.4 ohms; (b) 3.3 amp.; (c) Chapter 26, Section V : 47—-Page 302... |
11 9.7 cents 12 $1.12 13 6 cents, 406 5 220 volts 2 (a) 50:1; (b) (i) 6 (i) 0.498 10 4.3 9 6 cents INDEX Aberration, chromatic, 210, 224; spherical, 193 Abnormal expansion of water, 124 Absolute, temperature, 123; zero, 123, 132 Absorption of radiant energy, 133, 142 {Exp. 168) _ Absorption spectra, 219 Accommodation,... |
Area, measurement of, 10; of conductor and resistance, 288 Argon, 335 Aristotle, 1, 3, 49, 175 Armature, 321, 323, 377 Arrangement of cells, 283 Arrhenius, Svante, 295 Artificial, magnets, 260; transmutation of ele- ments, 399 Astigmatism, 230, 231 Astronomical telescope, 233, 234 {Exp. 254) Atmosphere, pressure of, 1... |
sea, 130, 131 Bridges, expansion in, 116 Brilliancy, 202 British system of measurement, 9 British thermal unit, 139, 401 Brushes, electric, 314, 321, 323 Bucket and cylinder, 39 Bunsen burner, 163, 164 Buoyancy, 24 Buoyant force, 24 Burette, 12 Burton, Dr. F., 395 Caesium, 219, 347 Calculations with approximate number... |
, 135 Cold light, 176, 218 Collimator tube, 219 Colour, blindness, 223; chart, 221; disc, 215; filters, 221; pigments, 221, 223 {Exp. 253); importance of, 213, 223; nature of, 220222; printing, 223, 224; television, 394; theories of, 220, 222; uses of, 223; vision, 223 Coloured lights, 222 Commutator, 314, 322, 323, 37... |
, 228 Corpuscular theory- of light, 181 Corrosion, 299 Cosmic rays, 132 Coulombs, 281 Crest, 52 Critical, angle, 200; pressure, 155; tempera- ture, 155 Crookes, Sir William, 341 Crookes’ tube, 383; dark space, 341 Crystalline lens, 228 Cubic measure, 10 Curie, Pierre and Marie, 397 Current, see electric alternating, di... |
Exp. 251) Displacement, 30 Dissociation, 295, 296 Distance formula, lens, 208; mirror, 192 Distilled water, 295, 373 Distinct vision, least distance of, 229, 231 Distribution of charges, 276 {Exp. 362) Distributor, 328 Diverging lens, 203 Diverging pencil, 176 Division, 14, 15 Doppler’s principle, 66 Drums, 87 Dry, cel... |
, 298 {Exp. 369) ; of water, 295, 296 {Exp. 367) ; of copper sulphate solution, 297 {Exp. 368) Electrolyte, 279, 295 Electrolytic cell, 295, 296, 367 Electromagnet, 52, 263, 304, 306 {Exp. 375) Electromagnetic, induction, 317, 318; inertia, 327 Electromagnetic, waves, 132, 181, 219, 347; spectrum, 217 Electromagnetism,... |
; determination of, 64, 65; of waves, 53; of various sources, 65; ultrasonic, 65, 92 Frequency modulation, 393 Friction, 156; electricity produced by, 268, 270 {Exp. 358) Fuels, 113, 137, 144 Fundamental, 69, 75 Furnace, electric, 337 Fuses, 333 Fusion, meaning of, 146; atomic, 401; heat of, 148 {Exp. 170) Future of so... |
111; specific heat, and 139-146 {Exp. temperature, 169) ; 119-121; thermometers, 119-122; transfer of, 126; theory of, 109, 110; and work, 156 Heat exchange, principle of, 137, 140; dur- radiation 172) ; {Exp. {Exp. 109, of, ing changes of state, 146 Heat from electric current, 331, 333 Heat from nuclear fission, 401 ... |
.M.F.) 318; cause of, 318 {Exp. 378); direction of, 319 {Exp. 380); self, 327 magnitude of, 318 {Exp. 379) ; {Exp. 382) Induced magnetism, 263, 264 {Exp. 354, 355) Induction, 263; charging electroscope by, 273, 274 {Exp. 362) Induction coil, 327 ; uses, 328, 383 Infra-red radiations, 132, 216 In parallel, 284, 312 Inpu... |
) Lead, 397, 398 ; spongy, 301 Lead-acid storage battery, 300 {Exp. 372) Lead peroxide, 301 Left-hand rule, 305 {Exp. 374) Length, measurement of, 7, 8, 9; of conduc- tor and resistance, 288 Lenses, accommodation, 229; action of, 203 {Exp. 250); applications of, 210; crystalline, 228; focal length of, 205 {Exp. 249); f... |
) ; 262, 306 Magnetism, 1, 259; induced, 263 {Exp. 354, 355) laws of, 260, 352 {Exp. 352); terrestrial, 260-263; theory of, 264 {Exp. 357) Magnetite, 259 Magnetization {Exp. 356) Magnification formula, lens, 208; mirror, 192 Magnifying glass, 231 412 Magnifying power, 231, 232, 233, 395 Major triad, 84 Make and break, ... |
strings, 69 {Exp. 100) Modulation, 347, 393 Molecules, 19, 112, 128, 132, 134, 152, 297; motion of, 110; kinetic theory of, 110 Molecular theory of magnetism, 265 {Exp. 357) Monochromatic light, 199; flame attachment, 253 Moseley, 398 Motor, principle, 309, 310 {Exp. 376, 377); St. Louis, 313; structure of, 313; direc... |
energy level), 269, 399 Organ, electric, 88; pipes, 85-87 Origin of sound, 49 Orthicon, 391 Oscillator, 347 Oscilloscope, sound tracings, 63, 70 Ounce, 10 Output, 112 Overflow can, 40, 43 Overtone, 69, 75, 86 Oxidizing agent, 280 Oxygen, 156, 295, 399 Parabola, 194 Parabolic mirrors, 194, 234 Parallax, method of, 34 P... |
permanganate, 128, 166 Potential, difference, 280-282; energy, 112 Pound, 10 Power, meaning, 337; of electric current, 324, 337; of lens, 205 Prefixes (metric), 9 Presbyopia, 231 Pressure, atmospheric, 120; cooker, 147; critical, 155; effect on boiling point, 147, 148; in water, 282 Primary, cells, 300; coil, 323, 378... |
132; gamma, 219, 398; infrared, 152, 216; light, 175, 176; ultra-violet, 132, 347 Reactors, nuclear, frontispiece, 401-403 Real image, 178, 207 Rear-vision mirror, 193 Receiver, telephone, 325 Receiving station, radio, 347 Reciprocating steam engine, 157 Recomposition of white light, 215 {Exp. 252) Recorder, sunlight,... |
175 South magnetic pole, 261 Spark, 326; discharge, 275; plugs, 328 Specific gravity, 20, 301 ; determination of, 27, 28 {Exp. 38, 41, 42) Specific-gravity bottle, 38 Specific heat, definition of, 139 {Exp. 169) Spectacles, 230 Spectra, 213, 214; kinds, 219 {Exp. 251) Spectroscope, 218, 219 Spectrum analysis, 219 {Exp... |
, 10; prefixes, 9; resistances, 288; specific gravities, 21; specific heats, 139; units of electricity, 282; velocity of sound and temperature, of sound in various media, 61; volume, 10; wave-lengths of coloured lights, 214 equivalents, velocity 298; 60; Tape recorder, 90 Telephone, 325, 326 Telescopes, 233, 234 {Exp. ... |
{Exp. l04) Tuning musical instruments, 79 Tungsten, 335 Turbines, 331; steam, 157 U, see Uranium below Ultrasonic frequencies, 65, 92 Ultra-violet, lamps, 218; radiation, 218; light, 132, 347 Umbra, 178 Unison, 79 Units, electrical, 282; heat, 138; measure- ment, 8-11; power, 337; sound, 64 Universal hydrometer, 28 Up... |
for secondary schoo 1 39903263 CURR HIST,X- CJ STUDENT ohool BASIC PHYSICS THE MACMILLAN COMPANY OF CANADA LIMITED checks (NOTE TO SELF: Add to this table as we go along with examples from each section.) Now you don’t have to memorise this table but you should read it. The best thing to do is to refer to it every time... |
| |----| |----| |----| |----| -269 Celsius -270 Celsius -271 Celsius -272 Celsius -273 Celsius |----| |----| |----| |----| |----| 4 Kelvin 3 Kelvin 2 Kelvin 1 Kelvin 0 Kelvin absolute zero ---> (NOTE TO SELF: Come up with a decent picture of two ladders with the labels |water boiling and freezing|in the same place but ... |
when the water is still and a trough is a place where the water sinks lower than when the water is still. A single peak or trough we call a pulse. A wave consists of a train of pulses. So waves have peaks and troughs. This could be our flrst property for waves. The following diagram shows the peaks and troughs on a wav... |
are in phase. Two points in phase are separate by an integer (0,1,2,3,...) number of complete wave cycles. They don’t have to be peaks or trough but they must be separated by a complete number of waves. 2.1.3 Characteristics of Waves : Period Now imagine you are sitting next to a pond and you watch the waves going pas... |
m:s¡1) : wavelength (m) : period (s) There are a number of relationships involving the various characteristic quantities of waves. A simple example of how this would be useful is how to determine the velocity when you have the frequency and the wavelength. We can take the above equation and substitute the relationship ... |
is created behind the peak. ØŁ æ Æ As this repeats we get waves of increased and decreased pressure moving down the tubes. We can describe these pulses of increased pressure (peaks in the pressure) and decreased pressure (troughs of pressure) by a sine or cosine graph. ´˜ˆ £¥⁄ ƒ¤§ ˇ— ¢¡ 14! " # $ % & ’ ( ) * +,. / Inc... |
into a mirror your see yourself reected directly back but if you tilt the mirror slightly you can experiment with difierent incident angles. Phase shift of reected wave When a wave is reected from a more dense medium it undergoes a phase shift. That means that the peaks and troughs are swapped around. The easiest way t... |
the angle of the wavefront is going to change. This is known as refraction. When a wave bends or changes its direction when it goes from one medium to the next. If it slows down it turns towards the perpendicular. 2 17 Air Water If the wave speeds up in the new medium it turns away from the perpendicular to the medium... |
can occur: standing waves can form. Standing waves are disturbances which don’t appear to move, they look like they stay in the same place even though the waves that from them are moving. Lets demonstrate exactly how this comes about. Imagine a long string with waves being sent down it from either end. The waves from ... |
top of the picture show peaks where maximum positive constructive interference is taking place. The arrows at the bottom of the picture show places where maximum negative interference is taking place. 1 0 -1 0 As time goes by the peaks become smaller and the troughs become shallower but they do not -3 -1 -2 -4 1 3 2 4... |
the envelope for the oscillations to describe the motion. We cannot draw the up and down arrows for every single point! Reection from a flxed end If waves are reected from a flxed end, for example tieing the end of a rope to a pole and then sending waves down it. The flxed end will always be a node. Remember: Waves reect... |
anti-nodes. If all of the tubes have a length L and we know the end constraints we can workout the wavelenth, ‚, for a speciflc number of anti-nodes. Lets workout the longest wavelength we can have in each tube, i.e. the case for n = 1. ‚ = 2L ‚ = 4L n = 1 Case 1: In the flrst tube both ends must be nodes so we can plac... |
1 2 ‚) = L ‚ = L Case 2: We want to have two nodes inside the tube. The left end must be a node and the right end must be an anti-node. We can have one node inside the tube as drawn above. Again we can count the number of distances between adjacent nodes or anti-nodes. If we start from the left end we have one half wa... |
be nodes. With one node in between there are two sets of adjacent nodes. This means that the length of the tube consists of two half wavelength sections: 2( 1 2 ‚) = L ‚ = L 2.3.5 Beats If the waves that are interfering are not identical then the waves form a modulated pattern with a changing amplitude. The peaks in a... |
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