Question

A pursuit spacecraft from the planet Tatooine is attempting to catch up with a Trade Federation cruiser. As measured by an observer on Tatooine, the cruiser is traveling away from the planet with a speed of 0.6c. The pursuit ship is traveling at a speed of 0.8c relative to Tatooine, in the same direction as the cruiser. What is the speed of the pursuit ship relative to the cruiser?

Answer 1

Answer:

0.384c

Explanation:

To find the speed of the pursuit ship relative to the cruiser you use the following relativistic equation:

$u'=\frac{u-v}{1-\frac{uv}{c^2}}$

u': relative speed

u: speed of the pursuit ship = 0.8c

v: speed of the cruiser = 0.6c

c: speed of light

You replace the values of the parameters to obtain u':

$u'=\frac{0.8c-0.6c}{1-\frac{(0.6c)(0.8c)}{c^2}}=0.384c$

Hence, the relative speed is 0.384c