id
stringlengths
24
24
title
stringclasses
442 values
context
stringlengths
151
3.71k
question
stringlengths
12
270
answers
dict
572ec623dfa6aa1500f8d384
Endangered_Species_Act
As of September 2012, fifty-six species have been delisted; twenty-eight due to recovery, ten due to extinction (seven of which are believed to have been extinct prior to being listed), ten due to changes in taxonomic classification practices, six due to discovery of new populations, one due to an error in the listing ...
Of the ten species removed due to extinction, how many are believe to have already been extinct when listed?
{ "answer_start": [ 113 ], "text": [ "seven" ] }
572ec623dfa6aa1500f8d385
Endangered_Species_Act
As of September 2012, fifty-six species have been delisted; twenty-eight due to recovery, ten due to extinction (seven of which are believed to have been extinct prior to being listed), ten due to changes in taxonomic classification practices, six due to discovery of new populations, one due to an error in the listing ...
How many species have been downgraded from endangered to threatened status?
{ "answer_start": [ 430 ], "text": [ "Twenty-five" ] }
572ec623dfa6aa1500f8d386
Endangered_Species_Act
As of September 2012, fifty-six species have been delisted; twenty-eight due to recovery, ten due to extinction (seven of which are believed to have been extinct prior to being listed), ten due to changes in taxonomic classification practices, six due to discovery of new populations, one due to an error in the listing ...
How many species were delisted due to discoveries of new populations?
{ "answer_start": [ 244 ], "text": [ "six" ] }
572ec6bccb0c0d14000f154b
Endangered_Species_Act
Opponents of the Endangered Species Act argue that with over 2,000 endangered species listed, and only 28 delisted due to recovery, the success rate of 1% over nearly three decades proves that there needs to be serious reform in their methods to actually help the endangered animals and plants. Others argue that the ESA...
How did a land owner impact the protected red-cockaded woodpecker species?
{ "answer_start": [ 653 ], "text": [ "increased harvesting and shortened the age at which he harvests his trees to ensure that they do not become old enough to become suitable habitat" ] }
572ec6bccb0c0d14000f1549
Endangered_Species_Act
Opponents of the Endangered Species Act argue that with over 2,000 endangered species listed, and only 28 delisted due to recovery, the success rate of 1% over nearly three decades proves that there needs to be serious reform in their methods to actually help the endangered animals and plants. Others argue that the ESA...
What is the success rate of the list and the Endangered Species Act initiatives?
{ "answer_start": [ 152 ], "text": [ "1%" ] }
572ec6bccb0c0d14000f154a
Endangered_Species_Act
Opponents of the Endangered Species Act argue that with over 2,000 endangered species listed, and only 28 delisted due to recovery, the success rate of 1% over nearly three decades proves that there needs to be serious reform in their methods to actually help the endangered animals and plants. Others argue that the ESA...
What is the name given to the act of pre-emptive habitat destruction by landowners fearing a protected species?
{ "answer_start": [ 490 ], "text": [ "\"Shoot, Shovel and Shut-Up.\"" ] }
572ec6bccb0c0d14000f1548
Endangered_Species_Act
Opponents of the Endangered Species Act argue that with over 2,000 endangered species listed, and only 28 delisted due to recovery, the success rate of 1% over nearly three decades proves that there needs to be serious reform in their methods to actually help the endangered animals and plants. Others argue that the ESA...
How many species are currently listed?
{ "answer_start": [ 56 ], "text": [ "over 2,000" ] }
572ec78cc246551400ce464c
Endangered_Species_Act
According to research published in 1999 by Alan Green and the Center for Public Integrity (CPI), loopholes in the ESA are commonly exploited in the exotic pet trade. Although the legislation prohibits interstate and foreign transactions for list species, no provisions are made for in-state commerce, allowing these anim...
What is one particular industry that exploits Endangered Species Act loopholes?
{ "answer_start": [ 148 ], "text": [ "exotic pet trade" ] }
572ec78cc246551400ce464d
Endangered_Species_Act
According to research published in 1999 by Alan Green and the Center for Public Integrity (CPI), loopholes in the ESA are commonly exploited in the exotic pet trade. Although the legislation prohibits interstate and foreign transactions for list species, no provisions are made for in-state commerce, allowing these anim...
What is one particular loophole that aids roadside zoos and private collectors?
{ "answer_start": [ 255 ], "text": [ "no provisions are made for in-state commerce" ] }
572ec78cc246551400ce464e
Endangered_Species_Act
According to research published in 1999 by Alan Green and the Center for Public Integrity (CPI), loopholes in the ESA are commonly exploited in the exotic pet trade. Although the legislation prohibits interstate and foreign transactions for list species, no provisions are made for in-state commerce, allowing these anim...
What allows exploitation of interstate commerce regulations?
{ "answer_start": [ 390 ], "text": [ "the ESA allows listed species to be shipped across state lines as long as they are not sold" ] }
572ec78cc246551400ce464f
Endangered_Species_Act
According to research published in 1999 by Alan Green and the Center for Public Integrity (CPI), loopholes in the ESA are commonly exploited in the exotic pet trade. Although the legislation prohibits interstate and foreign transactions for list species, no provisions are made for in-state commerce, allowing these anim...
How can fake breeding loans be used to sell wildlife?
{ "answer_start": [ 611 ], "text": [ "in return they can legally receive a reciprocal monetary \"donation\" from the receiving party." ] }
572ec78cc246551400ce4650
Endangered_Species_Act
According to research published in 1999 by Alan Green and the Center for Public Integrity (CPI), loopholes in the ESA are commonly exploited in the exotic pet trade. Although the legislation prohibits interstate and foreign transactions for list species, no provisions are made for in-state commerce, allowing these anim...
Why are there not more arrests from undercover investigations of interstate wildlife commerce?
{ "answer_start": [ 772 ], "text": [ "the US Fish and Wildlife Service revealed that the agency does not have sufficient staff to perform undercover investigations" ] }
572ec878dfa6aa1500f8d3af
Endangered_Species_Act
Green and the CPI further noted another exploit of the ESA in their discussion of the critically endangered cotton-top tamarin (Saguinus oedipus). Not only had they found documentation that 151 of these primates had inadvertently made their way from the Harvard-affiliated New England Regional Primate Research Center in...
The Center for Public Integrity found that 151 of what primate were moved from the New England Primate Research Center into exotic pet trade?
{ "answer_start": [ 108 ], "text": [ "cotton-top tamarin" ] }
572ec878dfa6aa1500f8d3b0
Endangered_Species_Act
Green and the CPI further noted another exploit of the ESA in their discussion of the critically endangered cotton-top tamarin (Saguinus oedipus). Not only had they found documentation that 151 of these primates had inadvertently made their way from the Harvard-affiliated New England Regional Primate Research Center in...
What happened in 1976 that impacted this primate's classification as Endanger?
{ "answer_start": [ 402 ], "text": [ "over 800 cotton-top tamarins were imported into the United States" ] }
572ec878dfa6aa1500f8d3b1
Endangered_Species_Act
Green and the CPI further noted another exploit of the ESA in their discussion of the critically endangered cotton-top tamarin (Saguinus oedipus). Not only had they found documentation that 151 of these primates had inadvertently made their way from the Harvard-affiliated New England Regional Primate Research Center in...
What school is affiliated with the New England Primate Research Center?
{ "answer_start": [ 254 ], "text": [ "Harvard" ] }
572ec920cb0c0d14000f155c
Endangered_Species_Act
Section 6 of the Endangered Species Act provided funding for development of programs for management of threatened and endangered species by state wildlife agencies. Subsequently, lists of endangered and threatened species within their boundaries have been prepared by each state. These state lists often include species ...
Section 6 of the Endangered Species Act provided funding for what purpose?
{ "answer_start": [ 61 ], "text": [ "development of programs for management of threatened and endangered species by state wildlife agencies" ] }
572ec920cb0c0d14000f155d
Endangered_Species_Act
Section 6 of the Endangered Species Act provided funding for development of programs for management of threatened and endangered species by state wildlife agencies. Subsequently, lists of endangered and threatened species within their boundaries have been prepared by each state. These state lists often include species ...
What is one notable drawback with state wildlife agencies creating their own lists?
{ "answer_start": [ 280 ], "text": [ "These state lists often include species which are considered endangered or threatened within a specific state but not within all states" ] }
572ec920cb0c0d14000f155e
Endangered_Species_Act
Section 6 of the Endangered Species Act provided funding for development of programs for management of threatened and endangered species by state wildlife agencies. Subsequently, lists of endangered and threatened species within their boundaries have been prepared by each state. These state lists often include species ...
What states are listing species that are endangered in their own state, but that are not endangered in all other states?
{ "answer_start": [ 530 ], "text": [ "Florida, Minnesota, Maine, and California" ] }
572ec9bf03f9891900756a25
Endangered_Species_Act
A reward will be paid to any person who furnishes information which leads to an arrest, conviction, or revocation of a license, so long as they are not a local, state, or federal employee in the performance of official duties. The Secretary may also provide reasonable and necessary costs incurred for the care of fish, ...
Is the public given incentive to report Endangered Species Act violations?
{ "answer_start": [ 0 ], "text": [ "A reward will be paid to any person who furnishes information which leads to an arrest, conviction, or revocation of a license" ] }
572ec9bf03f9891900756a26
Endangered_Species_Act
A reward will be paid to any person who furnishes information which leads to an arrest, conviction, or revocation of a license, so long as they are not a local, state, or federal employee in the performance of official duties. The Secretary may also provide reasonable and necessary costs incurred for the care of fish, ...
Given that a violator caused wildlife harm, who may provide financial assistance for the care of the harmed wildlife?
{ "answer_start": [ 227 ], "text": [ "The Secretary" ] }
572ec9bf03f9891900756a27
Endangered_Species_Act
A reward will be paid to any person who furnishes information which leads to an arrest, conviction, or revocation of a license, so long as they are not a local, state, or federal employee in the performance of official duties. The Secretary may also provide reasonable and necessary costs incurred for the care of fish, ...
Costs over what balance lead to the Secretary of the Treasury depositing money into the cooperative endangered species conservation fund?
{ "answer_start": [ 432 ], "text": [ "$500,000" ] }
572e9317cb0c0d14000f12e2
Vacuum
Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply ca...
The word Vacuum stems from what Latin adjective?
{ "answer_start": [ 72 ], "text": [ "vacuus" ] }
572e9317cb0c0d14000f12e3
Vacuum
Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply ca...
What does the term used by Physicists, partial vacuum, refer to?
{ "answer_start": [ 401 ], "text": [ "imperfect vacuum" ] }
572e9317cb0c0d14000f12e4
Vacuum
Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply ca...
What is a vacuum?
{ "answer_start": [ 10 ], "text": [ "space void of matter" ] }
572e9317cb0c0d14000f12e5
Vacuum
Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply ca...
What type of pressure is less than atmospheric pressure in a vacuum?
{ "answer_start": [ 154 ], "text": [ "gaseous" ] }
572e9317cb0c0d14000f12e6
Vacuum
Vacuum is space void of matter. The word stems from the Latin adjective vacuus for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply ca...
What Latin term is used to describe an object in a vacuum?
{ "answer_start": [ 619 ], "text": [ "in vacuo" ] }
572e95ba03f98919007567d9
Vacuum
The quality of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by around 20%. Much higher-quality vacuums are possible. Ultra-high vacuum chambe...
The Vacuum state is considered what?
{ "answer_start": [ 1015 ], "text": [ "the ground state of matter." ] }
572e95ba03f98919007567da
Vacuum
The quality of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by around 20%. Much higher-quality vacuums are possible. Ultra-high vacuum chambe...
A typical vacuum cleaner produces enough suction to do what to air pressure?
{ "answer_start": [ 219 ], "text": [ "reduce air pressure by around 20%" ] }
572e95ba03f98919007567db
Vacuum
The quality of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by around 20%. Much higher-quality vacuums are possible. Ultra-high vacuum chambe...
The quality of a partial vacuum refers to what?
{ "answer_start": [ 42 ], "text": [ "how closely it approaches a perfect vacuum" ] }
572e95ba03f98919007567dc
Vacuum
The quality of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by around 20%. Much higher-quality vacuums are possible. Ultra-high vacuum chambe...
Outer space has a high quality vacuum with what equivalent?
{ "answer_start": [ 557 ], "text": [ "a few hydrogen atoms per cubic meter" ] }
572e95ba03f98919007567dd
Vacuum
The quality of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by around 20%. Much higher-quality vacuums are possible. Ultra-high vacuum chambe...
If all matter is removed from a vacuum, would it be empty space?
{ "answer_start": [ 692 ], "text": [ "it would still not be \"empty\"" ] }
572e97a3dfa6aa1500f8d19f
Vacuum
Historically, there has been much dispute over whether such a thing as a vacuum can exist. Ancient Greek philosophers debated the existence of a vacuum, or void, in the context of atomism, which posited void and atom as the fundamental explanatory elements of physics. Following Plato, even the abstract concept of a fea...
What did Aristotle believe about a void?
{ "answer_start": [ 647 ], "text": [ "no void could occur naturally," ] }
572e97a3dfa6aa1500f8d1a0
Vacuum
Historically, there has been much dispute over whether such a thing as a vacuum can exist. Ancient Greek philosophers debated the existence of a vacuum, or void, in the context of atomism, which posited void and atom as the fundamental explanatory elements of physics. Following Plato, even the abstract concept of a fea...
What was historically disputed about vacuums?
{ "answer_start": [ 47 ], "text": [ "whether such a thing as a vacuum can exist." ] }
572e97a3dfa6aa1500f8d1a1
Vacuum
Historically, there has been much dispute over whether such a thing as a vacuum can exist. Ancient Greek philosophers debated the existence of a vacuum, or void, in the context of atomism, which posited void and atom as the fundamental explanatory elements of physics. Following Plato, even the abstract concept of a fea...
What did something that was literally nothing at all,According to Plato, mean?
{ "answer_start": [ 590 ], "text": [ "cannot rightly be said to exist" ] }
572e97a3dfa6aa1500f8d1a2
Vacuum
Historically, there has been much dispute over whether such a thing as a vacuum can exist. Ancient Greek philosophers debated the existence of a vacuum, or void, in the context of atomism, which posited void and atom as the fundamental explanatory elements of physics. Following Plato, even the abstract concept of a fea...
Aristotle thought what would fill any rarity that might give rise to a void?
{ "answer_start": [ 690 ], "text": [ "denser surrounding material continuum" ] }
572e99b7dfa6aa1500f8d1cf
Vacuum
In his Physics, book IV, Aristotle offered numerous arguments against the void: for example, that motion through a medium which offered no impediment could continue ad infinitum, there being no reason that something would come to rest anywhere in particular. Although Lucretius argued for the existence of vacuum in the ...
In what century did believes start to move away from Aristotle's idea regarding a void?
{ "answer_start": [ 670 ], "text": [ "14th century" ] }
572e99b7dfa6aa1500f8d1d0
Vacuum
In his Physics, book IV, Aristotle offered numerous arguments against the void: for example, that motion through a medium which offered no impediment could continue ad infinitum, there being no reason that something would come to rest anywhere in particular. Although Lucretius argued for the existence of vacuum in the ...
What thought process was used in the beginning belief of the existence of vacuums?
{ "answer_start": [ 620 ], "text": [ "Stoic physics" ] }
572e99b7dfa6aa1500f8d1d2
Vacuum
In his Physics, book IV, Aristotle offered numerous arguments against the void: for example, that motion through a medium which offered no impediment could continue ad infinitum, there being no reason that something would come to rest anywhere in particular. Although Lucretius argued for the existence of vacuum in the ...
Roger Bacon,Walter Burley and Blasius of Parma were from what century?
{ "answer_start": [ 525 ], "text": [ "13th and 14th" ] }
572e99b7dfa6aa1500f8d1d1
Vacuum
In his Physics, book IV, Aristotle offered numerous arguments against the void: for example, that motion through a medium which offered no impediment could continue ad infinitum, there being no reason that something would come to rest anywhere in particular. Although Lucretius argued for the existence of vacuum in the ...
What belief regarding a cosmic void was accepted by most in the 17th century?
{ "answer_start": [ 758 ], "text": [ "a supernatural void beyond the confines of the cosmos itself" ] }
572e9d48cb0c0d14000f136c
Vacuum
Rapid decompression can be much more dangerous than vacuum exposure itself. Even if the victim does not hold his or her breath, venting through the windpipe may be too slow to prevent the fatal rupture of the delicate alveoli of the lungs. Eardrums and sinuses may be ruptured by rapid decompression, soft tissues may br...
What does Rapid decompression do to the lungs?
{ "answer_start": [ 194 ], "text": [ "rupture of the delicate alveoli" ] }
572e9d48cb0c0d14000f136d
Vacuum
Rapid decompression can be much more dangerous than vacuum exposure itself. Even if the victim does not hold his or her breath, venting through the windpipe may be too slow to prevent the fatal rupture of the delicate alveoli of the lungs. Eardrums and sinuses may be ruptured by rapid decompression, soft tissues may br...
What causes barotrauma?
{ "answer_start": [ 439 ], "text": [ "rapid decompression" ] }
572e9d48cb0c0d14000f136e
Vacuum
Rapid decompression can be much more dangerous than vacuum exposure itself. Even if the victim does not hold his or her breath, venting through the windpipe may be too slow to prevent the fatal rupture of the delicate alveoli of the lungs. Eardrums and sinuses may be ruptured by rapid decompression, soft tissues may br...
What amount of pressure drop can kill you if it occurs suddenly?
{ "answer_start": [ 501 ], "text": [ "13 kPa (100 Torr)," ] }
572e9d48cb0c0d14000f136f
Vacuum
Rapid decompression can be much more dangerous than vacuum exposure itself. Even if the victim does not hold his or her breath, venting through the windpipe may be too slow to prevent the fatal rupture of the delicate alveoli of the lungs. Eardrums and sinuses may be ruptured by rapid decompression, soft tissues may br...
What does acceleration of oxygen consumption do?
{ "answer_start": [ 411 ], "text": [ "hypoxia" ] }
572e9d48cb0c0d14000f1370
Vacuum
Rapid decompression can be much more dangerous than vacuum exposure itself. Even if the victim does not hold his or her breath, venting through the windpipe may be too slow to prevent the fatal rupture of the delicate alveoli of the lungs. Eardrums and sinuses may be ruptured by rapid decompression, soft tissues may br...
rapid decompression is more dangerous than what?
{ "answer_start": [ 52 ], "text": [ "vacuum exposure" ] }
572eaab5cb0c0d14000f1428
Vacuum
Almost two thousand years after Plato, René Descartes also proposed a geometrically based alternative theory of atomism, without the problematic nothing–everything dichotomy of void and atom. Although Descartes agreed with the contemporary position, that a vacuum does not occur in nature, the success of his namesake co...
What did Descartes believe about vacuums in nature?
{ "answer_start": [ 250 ], "text": [ "that a vacuum does not occur in nature" ] }
572eaab5cb0c0d14000f1429
Vacuum
Almost two thousand years after Plato, René Descartes also proposed a geometrically based alternative theory of atomism, without the problematic nothing–everything dichotomy of void and atom. Although Descartes agreed with the contemporary position, that a vacuum does not occur in nature, the success of his namesake co...
Whose work with metaphysics would come to define the notion of empty space?
{ "answer_start": [ 201 ], "text": [ "Descartes" ] }
572eaab5cb0c0d14000f142a
Vacuum
Almost two thousand years after Plato, René Descartes also proposed a geometrically based alternative theory of atomism, without the problematic nothing–everything dichotomy of void and atom. Although Descartes agreed with the contemporary position, that a vacuum does not occur in nature, the success of his namesake co...
What philosophy combined with Descartes to push quantum activity in the 20th century?
{ "answer_start": [ 641 ], "text": [ "Cartesian mechanical philosophy" ] }
572eac6adfa6aa1500f8d295
Vacuum
In 1930, Paul Dirac proposed a model of the vacuum as an infinite sea of particles possessing negative energy, called the Dirac sea. This theory helped refine the predictions of his earlier formulated Dirac equation, and successfully predicted the existence of the positron, confirmed two years later. Werner Heisenberg'...
An infinite sea of particles with negative energy was a model propesed by whom?
{ "answer_start": [ 9 ], "text": [ "Paul Dirac" ] }
572eac6adfa6aa1500f8d296
Vacuum
In 1930, Paul Dirac proposed a model of the vacuum as an infinite sea of particles possessing negative energy, called the Dirac sea. This theory helped refine the predictions of his earlier formulated Dirac equation, and successfully predicted the existence of the positron, confirmed two years later. Werner Heisenberg'...
What year was the Dirac sea modeled?
{ "answer_start": [ 3 ], "text": [ "1930" ] }
572eac6adfa6aa1500f8d297
Vacuum
In 1930, Paul Dirac proposed a model of the vacuum as an infinite sea of particles possessing negative energy, called the Dirac sea. This theory helped refine the predictions of his earlier formulated Dirac equation, and successfully predicted the existence of the positron, confirmed two years later. Werner Heisenberg'...
When werer virtual particles confirmed?
{ "answer_start": [ 567 ], "text": [ "late 20th century" ] }
572eac6adfa6aa1500f8d298
Vacuum
In 1930, Paul Dirac proposed a model of the vacuum as an infinite sea of particles possessing negative energy, called the Dirac sea. This theory helped refine the predictions of his earlier formulated Dirac equation, and successfully predicted the existence of the positron, confirmed two years later. Werner Heisenberg'...
What year was the uncertainty principle formed?
{ "answer_start": [ 358 ], "text": [ "1927," ] }
572eac6adfa6aa1500f8d299
Vacuum
In 1930, Paul Dirac proposed a model of the vacuum as an infinite sea of particles possessing negative energy, called the Dirac sea. This theory helped refine the predictions of his earlier formulated Dirac equation, and successfully predicted the existence of the positron, confirmed two years later. Werner Heisenberg'...
What theorized that time and energy can be measured?
{ "answer_start": [ 302 ], "text": [ "Werner Heisenberg's uncertainty principle" ] }
572ead9cc246551400ce44de
Vacuum
In general relativity, a vanishing stress-energy tensor implies, through Einstein field equations, the vanishing of all the components of the Ricci tensor. Vacuum does not mean that the curvature of space-time is necessarily flat: the gravitational field can still produce curvature in a vacuum in the form of tidal forc...
what is a perfect example of a filled vacuum showing a curvature?
{ "answer_start": [ 417 ], "text": [ "The black hole" ] }
572ead9cc246551400ce44df
Vacuum
In general relativity, a vanishing stress-energy tensor implies, through Einstein field equations, the vanishing of all the components of the Ricci tensor. Vacuum does not mean that the curvature of space-time is necessarily flat: the gravitational field can still produce curvature in a vacuum in the form of tidal forc...
Who's equations helped to imply vanishing of the Ricci tensor?
{ "answer_start": [ 73 ], "text": [ "Einstein" ] }
572ead9cc246551400ce44e0
Vacuum
In general relativity, a vanishing stress-energy tensor implies, through Einstein field equations, the vanishing of all the components of the Ricci tensor. Vacuum does not mean that the curvature of space-time is necessarily flat: the gravitational field can still produce curvature in a vacuum in the form of tidal forc...
what produces curvature in a vacuum?
{ "answer_start": [ 310 ], "text": [ "tidal forces and gravitational waves" ] }
572ead9cc246551400ce44e1
Vacuum
In general relativity, a vanishing stress-energy tensor implies, through Einstein field equations, the vanishing of all the components of the Ricci tensor. Vacuum does not mean that the curvature of space-time is necessarily flat: the gravitational field can still produce curvature in a vacuum in the form of tidal forc...
What has no electric charge?
{ "answer_start": [ 421 ], "text": [ "black hole" ] }
572eaf28dfa6aa1500f8d2c1
Vacuum
But although it meets the definition of outer space, the atmospheric density within the first few hundred kilometers above the Kármán line is still sufficient to produce significant drag on satellites. Most artificial satellites operate in this region called low Earth orbit and must fire their engines every few days to...
Where do most satellites operate?
{ "answer_start": [ 259 ], "text": [ "low Earth orbit" ] }
572eaf28dfa6aa1500f8d2c2
Vacuum
But although it meets the definition of outer space, the atmospheric density within the first few hundred kilometers above the Kármán line is still sufficient to produce significant drag on satellites. Most artificial satellites operate in this region called low Earth orbit and must fire their engines every few days to...
What system could possibly be used for interplanetary travel?
{ "answer_start": [ 447 ], "text": [ "solar sails" ] }
572eaf28dfa6aa1500f8d2c3
Vacuum
But although it meets the definition of outer space, the atmospheric density within the first few hundred kilometers above the Kármán line is still sufficient to produce significant drag on satellites. Most artificial satellites operate in this region called low Earth orbit and must fire their engines every few days to...
why do satellites need to fire engines every few day to keep orbit?
{ "answer_start": [ 57 ], "text": [ "atmospheric density" ] }
572eaf28dfa6aa1500f8d2c4
Vacuum
But although it meets the definition of outer space, the atmospheric density within the first few hundred kilometers above the Kármán line is still sufficient to produce significant drag on satellites. Most artificial satellites operate in this region called low Earth orbit and must fire their engines every few days to...
above what line location in outer space to satellites orbit?
{ "answer_start": [ 127 ], "text": [ "Kármán line" ] }
572eb66fdfa6aa1500f8d2ef
Vacuum
In the medieval Middle Eastern world, the physicist and Islamic scholar, Al-Farabi (Alpharabius, 872–950), conducted a small experiment concerning the existence of vacuum, in which he investigated handheld plungers in water.[unreliable source?] He concluded that air's volume can expand to fill available space, and he s...
Al-Farabi concluded a perfect vacuum was incoherent using what?
{ "answer_start": [ 197 ], "text": [ "handheld plungers in water." ] }
572eb66fdfa6aa1500f8d2f0
Vacuum
In the medieval Middle Eastern world, the physicist and Islamic scholar, Al-Farabi (Alpharabius, 872–950), conducted a small experiment concerning the existence of vacuum, in which he investigated handheld plungers in water.[unreliable source?] He concluded that air's volume can expand to fill available space, and he s...
Ibn al-Haytham used geometry to demonstrate what?
{ "answer_start": [ 645 ], "text": [ "place (al-makan) is the imagined three-dimensional void between the inner surfaces of a containing body" ] }
572eb66fdfa6aa1500f8d2f1
Vacuum
In the medieval Middle Eastern world, the physicist and Islamic scholar, Al-Farabi (Alpharabius, 872–950), conducted a small experiment concerning the existence of vacuum, in which he investigated handheld plungers in water.[unreliable source?] He concluded that air's volume can expand to fill available space, and he s...
who stated that there was no evidence to rule out a vacuum?
{ "answer_start": [ 777 ], "text": [ "Abū Rayhān al-Bīrūnī" ] }
572eb66fdfa6aa1500f8d2f2
Vacuum
In the medieval Middle Eastern world, the physicist and Islamic scholar, Al-Farabi (Alpharabius, 872–950), conducted a small experiment concerning the existence of vacuum, in which he investigated handheld plungers in water.[unreliable source?] He concluded that air's volume can expand to fill available space, and he s...
what did Al-Farabi say expanded to fill available space
{ "answer_start": [ 263 ], "text": [ "air's volume" ] }
572eb66fdfa6aa1500f8d2f3
Vacuum
In the medieval Middle Eastern world, the physicist and Islamic scholar, Al-Farabi (Alpharabius, 872–950), conducted a small experiment concerning the existence of vacuum, in which he investigated handheld plungers in water.[unreliable source?] He concluded that air's volume can expand to fill available space, and he s...
What type of pump appeared in the 15th century?
{ "answer_start": [ 895 ], "text": [ "suction pump" ] }
572ebaa3cb0c0d14000f14d4
Vacuum
Medieval thought experiments into the idea of a vacuum considered whether a vacuum was present, if only for an instant, between two flat plates when they were rapidly separated. There was much discussion of whether the air moved in quickly enough as the plates were separated, or, as Walter Burley postulated, whether a ...
Who required no restrictions regarding God's power?
{ "answer_start": [ 585 ], "text": [ "Bishop Etienne Tempier" ] }
572ebaa3cb0c0d14000f14d5
Vacuum
Medieval thought experiments into the idea of a vacuum considered whether a vacuum was present, if only for an instant, between two flat plates when they were rapidly separated. There was much discussion of whether the air moved in quickly enough as the plates were separated, or, as Walter Burley postulated, whether a ...
When did Buridan state that teams of ten horses could not open a bellow with a sealed port?
{ "answer_start": [ 779 ], "text": [ "14th century" ] }
572ebaa3cb0c0d14000f14d6
Vacuum
Medieval thought experiments into the idea of a vacuum considered whether a vacuum was present, if only for an instant, between two flat plates when they were rapidly separated. There was much discussion of whether the air moved in quickly enough as the plates were separated, or, as Walter Burley postulated, whether a ...
the 1277 Paris Condemnations led to what conclusion?
{ "answer_start": [ 707 ], "text": [ "God could create a vacuum if he so wished." ] }
572ebaa3cb0c0d14000f14d7
Vacuum
Medieval thought experiments into the idea of a vacuum considered whether a vacuum was present, if only for an instant, between two flat plates when they were rapidly separated. There was much discussion of whether the air moved in quickly enough as the plates were separated, or, as Walter Burley postulated, whether a ...
What was a common belief about vacuums and nature?
{ "answer_start": [ 396 ], "text": [ "nature abhorred a vacuum" ] }
572ebaa3cb0c0d14000f14d8
Vacuum
Medieval thought experiments into the idea of a vacuum considered whether a vacuum was present, if only for an instant, between two flat plates when they were rapidly separated. There was much discussion of whether the air moved in quickly enough as the plates were separated, or, as Walter Burley postulated, whether a ...
what was the belief that nature abhorred a vaccuum called?
{ "answer_start": [ 432 ], "text": [ "horror vacui" ] }
572ebcb4c246551400ce45b8
Vacuum
In 1654, Otto von Guericke invented the first vacuum pump and conducted his famous Magdeburg hemispheres experiment, showing that teams of horses could not separate two hemispheres from which the air had been partially evacuated. Robert Boyle improved Guericke's design and with the help of Robert Hooke further develope...
What was the vacuum created by the mercury displacement pump?
{ "answer_start": [ 537 ], "text": [ "partial vacuum of about 10 Pa (0.1 Torr)." ] }
572ebcb4c246551400ce45b9
Vacuum
In 1654, Otto von Guericke invented the first vacuum pump and conducted his famous Magdeburg hemispheres experiment, showing that teams of horses could not separate two hemispheres from which the air had been partially evacuated. Robert Boyle improved Guericke's design and with the help of Robert Hooke further develope...
What year was the Toepler Pump invented?
{ "answer_start": [ 404 ], "text": [ "1850" ] }
572ebcb4c246551400ce45ba
Vacuum
In 1654, Otto von Guericke invented the first vacuum pump and conducted his famous Magdeburg hemispheres experiment, showing that teams of horses could not separate two hemispheres from which the air had been partially evacuated. Robert Boyle improved Guericke's design and with the help of Robert Hooke further develope...
What was first invented by Otto von Guericke ?
{ "answer_start": [ 46 ], "text": [ "vacuum pump" ] }
572ebcb4c246551400ce45bb
Vacuum
In 1654, Otto von Guericke invented the first vacuum pump and conducted his famous Magdeburg hemispheres experiment, showing that teams of horses could not separate two hemispheres from which the air had been partially evacuated. Robert Boyle improved Guericke's design and with the help of Robert Hooke further develope...
Who conducted the Magdeburg experiment?
{ "answer_start": [ 9 ], "text": [ "Otto von Guericke" ] }
572ebcb4c246551400ce45bc
Vacuum
In 1654, Otto von Guericke invented the first vacuum pump and conducted his famous Magdeburg hemispheres experiment, showing that teams of horses could not separate two hemispheres from which the air had been partially evacuated. Robert Boyle improved Guericke's design and with the help of Robert Hooke further develope...
What was made visible at a partial vacuum of 10 Pa?
{ "answer_start": [ 579 ], "text": [ "A number of electrical properties" ] }
572ebe0a03f98919007569d1
Vacuum
While outer space provides the most rarefied example of a naturally occurring partial vacuum, the heavens were originally thought to be seamlessly filled by a rigid indestructible material called aether. Borrowing somewhat from the pneuma of Stoic physics, aether came to be regarded as the rarefied air from which it to...
What was originally believed the heavens were filled with?
{ "answer_start": [ 196 ], "text": [ "aether" ] }
572ebe0a03f98919007569d2
Vacuum
While outer space provides the most rarefied example of a naturally occurring partial vacuum, the heavens were originally thought to be seamlessly filled by a rigid indestructible material called aether. Borrowing somewhat from the pneuma of Stoic physics, aether came to be regarded as the rarefied air from which it to...
Why were experiments done on luminiferous aether in the 19 Century?
{ "answer_start": [ 901 ], "text": [ "\"While the interstellar absorbing medium may be simply the ether, [it] is characteris" ] }
572ebe0a03f98919007569d3
Vacuum
While outer space provides the most rarefied example of a naturally occurring partial vacuum, the heavens were originally thought to be seamlessly filled by a rigid indestructible material called aether. Borrowing somewhat from the pneuma of Stoic physics, aether came to be regarded as the rarefied air from which it to...
Who stated that the character of a gas and free molecule were in ether?
{ "answer_start": [ 874 ], "text": [ "Henry Pickering" ] }
572ebe0a03f98919007569d4
Vacuum
While outer space provides the most rarefied example of a naturally occurring partial vacuum, the heavens were originally thought to be seamlessly filled by a rigid indestructible material called aether. Borrowing somewhat from the pneuma of Stoic physics, aether came to be regarded as the rarefied air from which it to...
Where are the highest amounts of naturally occurring partial vacuums?
{ "answer_start": [ 6 ], "text": [ "outer space" ] }
572ebe0a03f98919007569d5
Vacuum
While outer space provides the most rarefied example of a naturally occurring partial vacuum, the heavens were originally thought to be seamlessly filled by a rigid indestructible material called aether. Borrowing somewhat from the pneuma of Stoic physics, aether came to be regarded as the rarefied air from which it to...
What was ether originally thought to be made of?
{ "answer_start": [ 159 ], "text": [ "rigid indestructible material" ] }
572ebf10c246551400ce45e6
Vacuum
The quality of a vacuum is indicated by the amount of matter remaining in the system, so that a high quality vacuum is one with very little matter left in it. Vacuum is primarily measured by its absolute pressure, but a complete characterization requires further parameters, such as temperature and chemical composition....
What indicated the quality of a vacuum?
{ "answer_start": [ 44 ], "text": [ "amount of matter remaining in the system" ] }
572ebf10c246551400ce45e7
Vacuum
The quality of a vacuum is indicated by the amount of matter remaining in the system, so that a high quality vacuum is one with very little matter left in it. Vacuum is primarily measured by its absolute pressure, but a complete characterization requires further parameters, such as temperature and chemical composition....
How is vacuum generally measured?
{ "answer_start": [ 191 ], "text": [ "its absolute pressure" ] }
572ebf10c246551400ce45e8
Vacuum
The quality of a vacuum is indicated by the amount of matter remaining in the system, so that a high quality vacuum is one with very little matter left in it. Vacuum is primarily measured by its absolute pressure, but a complete characterization requires further parameters, such as temperature and chemical composition....
What does the MFP of residual gases show?
{ "answer_start": [ 425 ], "text": [ "average distance that molecules will travel between collisions with each other." ] }
572ebf10c246551400ce45e9
Vacuum
The quality of a vacuum is indicated by the amount of matter remaining in the system, so that a high quality vacuum is one with very little matter left in it. Vacuum is primarily measured by its absolute pressure, but a complete characterization requires further parameters, such as temperature and chemical composition....
What is particle gas dynamics?
{ "answer_start": [ 751 ], "text": [ "study of fluid flows" ] }
572ec078c246551400ce460a
Vacuum
The SI unit of pressure is the pascal (symbol Pa), but vacuum is often measured in torrs, named for Torricelli, an early Italian physicist (1608–1647). A torr is equal to the displacement of a millimeter of mercury (mmHg) in a manometer with 1 torr equaling 133.3223684 pascals above absolute zero pressure. Vacuum is of...
Absolute pressure being equal to current atmospheric pressure means what?
{ "answer_start": [ 544 ], "text": [ "\"Below atmospheric\"" ] }
572ec078c246551400ce460b
Vacuum
The SI unit of pressure is the pascal (symbol Pa), but vacuum is often measured in torrs, named for Torricelli, an early Italian physicist (1608–1647). A torr is equal to the displacement of a millimeter of mercury (mmHg) in a manometer with 1 torr equaling 133.3223684 pascals above absolute zero pressure. Vacuum is of...
What is a torr equal to?
{ "answer_start": [ 175 ], "text": [ "displacement of a millimeter of mercury" ] }
572ec078c246551400ce460c
Vacuum
The SI unit of pressure is the pascal (symbol Pa), but vacuum is often measured in torrs, named for Torricelli, an early Italian physicist (1608–1647). A torr is equal to the displacement of a millimeter of mercury (mmHg) in a manometer with 1 torr equaling 133.3223684 pascals above absolute zero pressure. Vacuum is of...
What is another often used options to measure vacuum?
{ "answer_start": [ 345 ], "text": [ "barometric scale" ] }
572ec1b6c246551400ce461a
Vacuum
Hydrostatic gauges (such as the mercury column manometer) consist of a vertical column of liquid in a tube whose ends are exposed to different pressures. The column will rise or fall until its weight is in equilibrium with the pressure differential between the two ends of the tube. The simplest design is a closed-end U...
Why is mercury the better option for liquid used in a Hydrostatic gauge?
{ "answer_start": [ 444 ], "text": [ "its high density and low vapour pressure" ] }
572ec1b6c246551400ce461b
Vacuum
Hydrostatic gauges (such as the mercury column manometer) consist of a vertical column of liquid in a tube whose ends are exposed to different pressures. The column will rise or fall until its weight is in equilibrium with the pressure differential between the two ends of the tube. The simplest design is a closed-end U...
What is a vertical column of liquid in a tube which has different pressures at each end called?
{ "answer_start": [ 0 ], "text": [ "Hydrostatic gauges" ] }
572ec1b6c246551400ce461c
Vacuum
Hydrostatic gauges (such as the mercury column manometer) consist of a vertical column of liquid in a tube whose ends are exposed to different pressures. The column will rise or fall until its weight is in equilibrium with the pressure differential between the two ends of the tube. The simplest design is a closed-end U...
What is a hydrostatic gauge used for?
{ "answer_start": [ 516 ], "text": [ "measure pressures ranging from 1 torr (100 Pa) to above atmospheric" ] }
572ec1b6c246551400ce461d
Vacuum
Hydrostatic gauges (such as the mercury column manometer) consist of a vertical column of liquid in a tube whose ends are exposed to different pressures. The column will rise or fall until its weight is in equilibrium with the pressure differential between the two ends of the tube. The simplest design is a closed-end U...
Why is the McLeod gauge special?
{ "answer_start": [ 758 ], "text": [ "can measure vacuums as high as 10−6 torr" ] }
572ec1b6c246551400ce461e
Vacuum
Hydrostatic gauges (such as the mercury column manometer) consist of a vertical column of liquid in a tube whose ends are exposed to different pressures. The column will rise or fall until its weight is in equilibrium with the pressure differential between the two ends of the tube. The simplest design is a closed-end U...
An indirect measurement of pressure is most often calibrated by what?
{ "answer_start": [ 1117 ], "text": [ "McLeod gauge" ] }
572ec300c246551400ce4624
Vacuum
Thermal conductivity gauges rely on the fact that the ability of a gas to conduct heat decreases with pressure. In this type of gauge, a wire filament is heated by running current through it. A thermocouple or Resistance Temperature Detector (RTD) can then be used to measure the temperature of the filament. This temper...
The fact that gases ability to conduct heat decreases with pressure is used by what form of measurement?
{ "answer_start": [ 0 ], "text": [ "Thermal conductivity gauges" ] }
572ec300c246551400ce4625
Vacuum
Thermal conductivity gauges rely on the fact that the ability of a gas to conduct heat decreases with pressure. In this type of gauge, a wire filament is heated by running current through it. A thermocouple or Resistance Temperature Detector (RTD) can then be used to measure the temperature of the filament. This temper...
How is the wire filament in a Thermal conductivity gauge heated?
{ "answer_start": [ 161 ], "text": [ "by running current through it" ] }
572ec300c246551400ce4626
Vacuum
Thermal conductivity gauges rely on the fact that the ability of a gas to conduct heat decreases with pressure. In this type of gauge, a wire filament is heated by running current through it. A thermocouple or Resistance Temperature Detector (RTD) can then be used to measure the temperature of the filament. This temper...
What is a Pirani gauge sensitive to?
{ "answer_start": [ 645 ], "text": [ "chemical composition of the gases being measured" ] }
572ec300c246551400ce4627
Vacuum
Thermal conductivity gauges rely on the fact that the ability of a gas to conduct heat decreases with pressure. In this type of gauge, a wire filament is heated by running current through it. A thermocouple or Resistance Temperature Detector (RTD) can then be used to measure the temperature of the filament. This temper...
What is a RTD used for on a Thermal Conductivity gauge?
{ "answer_start": [ 265 ], "text": [ "to measure the temperature of the filament" ] }
572ec300c246551400ce4628
Vacuum
Thermal conductivity gauges rely on the fact that the ability of a gas to conduct heat decreases with pressure. In this type of gauge, a wire filament is heated by running current through it. A thermocouple or Resistance Temperature Detector (RTD) can then be used to measure the temperature of the filament. This temper...
A Pirani gauge is accurate within what ranges?
{ "answer_start": [ 593 ], "text": [ "10 torr to 10−3 torr" ] }
572ec42ecb0c0d14000f151b
Vacuum
Ion gauges are used in ultrahigh vacuum. They come in two types: hot cathode and cold cathode. In the hot cathode version an electrically heated filament produces an electron beam. The electrons travel through the gauge and ionize gas molecules around them. The resulting ions are collected at a negative electrode. The ...
What affects the number of ions in a gauge?
{ "answer_start": [ 376 ], "text": [ "the pressure in the gauge" ] }
572ec42ecb0c0d14000f151d
Vacuum
Ion gauges are used in ultrahigh vacuum. They come in two types: hot cathode and cold cathode. In the hot cathode version an electrically heated filament produces an electron beam. The electrons travel through the gauge and ionize gas molecules around them. The resulting ions are collected at a negative electrode. The ...
What must be used for accurate measurement on the composition of gases at a high vacuums?
{ "answer_start": [ 998 ], "text": [ "mass spectrometer must be used in conjunction with the ionization gauge" ] }
572ec42ecb0c0d14000f151c
Vacuum
Ion gauges are used in ultrahigh vacuum. They come in two types: hot cathode and cold cathode. In the hot cathode version an electrically heated filament produces an electron beam. The electrons travel through the gauge and ionize gas molecules around them. The resulting ions are collected at a negative electrode. The ...
What gauge is accurate from 10-2 torr to 10-9 torr?
{ "answer_start": [ 618 ], "text": [ "Cold cathode gauges" ] }