The spaceship Enterprise I is moving directly away from the earth at a speed that an earth bound observer measures at 0.65c. A sister ship, Enterprise I, is also moving directly away from the earth and is travelling faster than the Enterprise I. The relative speed between the ships is 0.31c. What is the speed of the Enterprise II, as measured by an earth-bound observer?

Question

anonymous · Answer

.65+31= .96

anonymous · Answer

.96c

poofypenguin · Answer

Is it really that simple? I'm not sure where the relative speed of 0.31c is measured from...does it make a difference if this relative speed is measured from the earth or from the first ship?

anonymous · Answer

it will take me a minute to figure this out, bare with me

poofypenguin · Answer

It's alright. Take your time :)

anonymous · Answer

Yes I am 100% positive it is .96c 

.96-.65=.31 (the relative speed)

poofypenguin · Answer

Thanks for your help!