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

Say, there are two bodies, mass m_{1}and m_{2}, initially at rest at infinite separation. They start accelerating towards each other because of gravity. Express the relative velocity of approach as a function of the distance between the two bodies.

2. Relevant equations

Laws of Motion, Law of Universal Gravitation, Conservation of Momentum and Energy.

3. The attempt at a solution

I thought the loss of gravitational potential energy should equal the gain in kinetic energy of the two bodies, so [itex]\frac{1}{2}(m_1 v_1^2 + m_2 v_2^2) = \frac{Gm_1 m_2}{r}[/itex]. Also, because of conservation of momentum, m_{1}v_{1}= m_{2}v_{2}, because the two objects have zero initial momentum. But I can't figure out the velocities from these two; and I think that's what i need.

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# Homework Help: Two bodies attracting via gravitation

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