Why do firemen use infrared cameras to look into smoke filled buildings?
A) The smoke itself gives off a lot of infrared light.
B) They can avoid all the broken glass because glass is bright in infrared light.
C) They can see through the smoke to look for people inside the room.
D) They can see if there is anything radioactive in the room.
E) They can tell if the smoke is toxic.
Ans: C) They can see through the smoke to look for people inside the room.
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The magnetic fields of Uranus and Neptune are peculiar in that they are
a. highly inclined to their planet's axis of rotation. b. very weak (virtually zero). c. produced by the solar wind. d. produced by disturbances caused by the orbits of the moons. e. all of the above.
In the context of a big bang model, identify a true statement about the flatness problem
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Magnetic confinement is used in controlled fusion experiments to
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