(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A spaceship, at rest in a certain reference frame S, is given a speed increment of 0.50c.

Relative to its new rest frame, it is then given a further 0.50c increment. This process is

continued until its speed with respect to its original frame S exceeds 0.999c. How many

increments does this process require?

2. Relevant equations

Velocity addition formula

(u + v)/(1 + uv/c^2)

3. The attempt at a solution

Speed after 1 increment = 0.50 c

Speed after 2 increments = (0.50 + 0.50) * c/(1 + 0.50*0.50)

= 0.80 c

Speed after 3 increments = (0.80 + 0.50)*c/(1 + 0.80*0.50)

= (13/14) c

But problem is I do not know how long to continue like this. Is there a simpler approach? I am not able to find if there is a generic expression for the velocity after nth increment for any given value of n.

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# Homework Help: Special relativity - A problem on velocity addition (several increments)

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