Velocity Addition: Consider three galaxies, Alpha, Beta and Gamma. An astronomer in Beta sees each of the other two galaxies moving away from him in opposite directions at 0.70c. At what speed would an observer in Alpha see the galaxy Gamma moving?

A. 0.70c
B. 1.4c
C. 0.82c
D. 0.94c
E. 0.98c


Answer: D

Physics & Space Science

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