PHYS 3310 Module 1 Activity 3

Suppose you measure the length of a spaceship, at rest relative to you, to be 400 m.

(a) How long will you measure it to be if it flies past you at a speed of u = 0.75c?

(b) The spaceship has a large clock attached to its side. This clock ran at the same rate as your watch when you were in the same reference frame. How much time will pass on your watch as 80 s passes on the clock attached to the ship?

Two spaceships named A and B are flying toward each other with relative speed of 0.800c.

(a) If the captain of ship A fires a missile, counts 10 s on his watch, and then fires a second missile, how much time will the captain of ship B measure to have passed between the firing of the two missiles?

(b) The captain of ship B knows that ship A uses 2-m-long missiles. She measures the length of the first missile, once it has finished accelerating, and finds it to be only 0.872 m long. What is the speed of the missile relative to ship B?