Question

The fictional rocket ship Adventure is measured to be 60 m

m

long by the ship's captain inside the rocket.When the rocket moves past a space dock at 0.5c

c

. As rocket ship Adventure passes by the space dock, the ship's captain flashes a flashlight at 1.40-s

s

intervals as measured by space-dock personnel.

How often does the flashlight flash relative to the captain?

Answer 1

from time dilation equation

to= t sqrt 1- ( v/c)^2

=(1.6 s) sqrt 1- (0.5 c/c)^2

=1.385 s