A rocket approaches a mirror on the ground at a speed of 0.90c. The distance D between the front of the rocket and the mirror is 2.4 * 10^12 m, as measured by ground observers, when a light signal is sent from the front of teh rocket. When is the reflected signal recieved by the rocket as measured by(adsbygoogle = window.adsbygoogle || []).push({});

a) the observers on the ground

b) the observers on the rocket?

I tried for a) working out the time interval using the formula and substituting the values known of speed of rocket and distance of rocket from mirror but I ended up with a huge value. The actual answer is given as 8.42n * 10^3 s and I am unaware how to get to this.

Can anybody give me some help?

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# Homework Help: Relativistic Kinematics

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