Space-Time Lab - Tutor Page 10
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Answer: B) While the rocket jets away from earth, to the astronaut everything is as Newton's relativity would predict: nothing unusual is happening. If there is then they would know that they were moving. However, the observer notices that, oddly the horizontal rods have contracted. Why did they contract? Because if they hadn't, going back to the Michelson-Morley experiment, if they hadn't then one photon would have returned first by traveling faster than 186,000 miles per second (Making the event dependent). This contraction simply removes that gamma speed-up predicted by Michelson-Morley (and experienced by the sailor), by contracting the distance traveled. You could argue that this is simply an illusion, if you asked the astronaut whether he was contracted in any way he would answer no. However this is not an optical illusion, it is real, or as real as Special Relativity gets. It is not an optical illusion, but perhaps an illusion playing on the limits of our perception. (I can't 'see' 4-D Space-Time, can you? :) ) Now here's another question - while the rocket moves farther from the earth, the astronaut happens to looks back at earth. What does HE see? A) The earth's frame is longer, by a factor of gamma, in the direction of its motion relative to the astronaut. B) The earth looks normal, because it's not moving. C) The earth's frame is contracted, by a factor gamma, in the direction of its motion relative to the astronaut. Choose a letter and Click Next. |
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