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If radio waves were used to communicate with an alien spaceship approaching Earth at 10% of the speed of light c, Earth would receive their signals at a speed of

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Answer:

Step-by-step explanation:

speed of alien spaceship = .1 c

We shall apply formula of relativistic mechanics to solve the problem

relative velocity =


(v+v_1)/(1 -(v* v )/(c^2) )

Here v = v₁ = .1 c

relative velocity = .1c + .1 c / 1 - .1²

= .2 c / .99

= .202 c

The earth would receive the signal at the speed of .202 c .

User V Maharajh
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