You are racing away from Earth in a super spaceship in which you can continually increase your speed. Which of the following best explains how people on Earth will perceive your speed?
A) They will know you are going very fast but will have no way of knowing whether you ever exceed the speed of light.
B) You will see any beam of light from Earth coming toward you at the speed of light, which means it will catch you. Thus, the people on Earth must conclude that you are going slower than the speed of light.
C) An imaginary spaceship can go as fast as it wants, so the folks on Earth soon will see you going faster than the speed of light.
D) You may soon be racing away from Earth faster than the speed of light, but, if so, people on Earth will no longer be able to see you.
E) Without more information, it is impossible to know how fast you would see a light beam from Earth coming toward you. If it happens that you are going fast enough so that the light can't catch you, then people on Earth would find you to be going faster than light.
Question 2
A basketball player jumps to make a basket, and remains in the air for a moment. A sportscaster, talking about the game, then remarks that she has defied gravity. Which of the following accurately describes the situation?
A) The player did stay in the air in spite of the Law of Gravitation, but a single counter-observation is not enough to warrant revisiting a theory that usually works.
B) The player produced enough force with her legs to accelerate up into the air, and gravity brought her back down with an acceleration of 9.8 m/s2.
C) The player only seemed to defy gravity, but part of the Universal Law of Gravitation makes an exception for basketball players.
D) The player has defied gravity, so scientists must go back into the lab to refine their theory.
Tides on Earth
Lightning on Earth
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