Question

Before it leaves Earth you observe the length of another spacecraft to be 200 m. After take-off, the craft travels past Earth (to wave good bye!) while moving at a velocity of 95% of the speed of light. You are assigned the task of re-measuring its length as it travels past.

a) Explain, at a fundamental level (i.e. with the principles of relativity in mind), how must you perform this measurement?

b) What value will you obtain? (ANS: 62m)