Aspaceship traveling to alpha centauri at 0.75c sends a message home to earth saying they are at the halfway point.
(a) what is the frequency (in ghz) of the message that earth listeners receive if it was sent at 9.4 ghz?
ghz
(b) if the ship's transmitter is omnidirectional, what is the frequency (in ghz) measured at alpha centauri?
ghz

(a) 24.87 GHz (b) 3.55 GHz

Explanation:

We have given the speed of the spaceship =0.75 c, here c is the speed of the light

(a) In the first case the ship is moving towards the alpha century

So the frequency is given by  

(b) In this case the ship is moving away from the alpha century

So frequency is given by

the components of a vector are the parts of the vectors that are to each other.

b perpendicular

answer a fan shaped mass of sediment deposited at the base of a mountain front do to an abrupt change in stream gradient;