Question

If a spaceship is approaching the earth at 0.38c and a message capsule is sent toward it at 0.38c relative to the earth, what is the speed of the capsule relative to the ship?

Answer 1

Here ,

speed of spaceship , v = 0.38 c

speed of capsule , u' = 0.38c

For the speed of capsule

u = (v + u')/(1 + v * u'/c^2)

u = (0.38 c + 0.38 * c)/(1 + 0.38 c * 0.38 *c/c^2)

u = 0.664 *c

the speed of the capsule relative to the ship is 0.664 c