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,
[tex]l = l_{0} \sqrt{1 - \beta ^{2} }[/tex]
where [tex]\beta = \frac{v}{c}[/tex]
[tex]l[/tex] is the relativistic length
[tex]l_{0}[/tex] 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
[tex]l = 400 * \sqrt{1 - 0.75 ^{2} }[/tex] = 400 x 0.66 = 264 m
