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

An electron and positron have mass m_{e}and separation R and are initially at rest. Find the time T it takes for them to collide.

2. Relevant equations

F=kq_{1}q_{2}/R^{2}

3. The attempt at a solution

My problem is that the force is not constant. Do I integrate the force then? And from what bounds?

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# Time it takes for an electron and proton to collide

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