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

A pendulum of mass m_1 is released at an angle theta_1 and strikes the pendulum of mass m_2, which rises to angle theta_2. The coefficient of restitution e for the two masses is given. Derive an expression for the angle theta_2.

2. Relevant equations

KE_1+PE_1=KE_2+PE_2

e=(v_{2}'-v_{1}')/(v_{1}-v_{2})

3. The attempt at a solution

Solving for v_{1}at time of impact using conservation of energy I get v_{1}=Sqrt(2gl(1-cos(theta_1)))

I solve the same equation for v'_{2}=sqrt(2gl(1-cos(theta_2)))

I then plug in the coefficient of restitution equation and solve for theta_2

theta_2= arccos(1-((e*Sqrt(2gl(1-cos(theta_1)))+v'_{1})^2)/2gl

My issue is determining whether or not this is a complete elastic collision. If so I assume the v'_{1}would be omitted, correct?

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# Homework Help: 2 swinging balls (pendulum) problem

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