Question

Suppose that you measure the length of a spaceship, at rest relative to you, to be 400 m. How long will you measure it to be if it flies past you at a speed of v

Answer 1

Answer:

264 m

Explanation:

The complete question is

Suppose that you measure the length of a spaceship, at rest relative to you, to be 400 m. How long will you measure it to be if it flies past you at a speed of v = 0.75c

using the length contraction relationship,

$l = l_{0} \sqrt{1 - \beta ^{2} }$

where $\beta = \frac{v}{c}$

$l$ is the relativistic length

$l_{0}$ is the actual length = 400 m

v is the velocity of the spaceship

c is the speed of light

since v = 0.75c

v/c = 0.75

substituting, we have

$l = 400 * \sqrt{1 - 0.75 ^{2} }$ = 400 x 0.66 = 264 m