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- Homework Statement
- A coin of radius R and mass M has a point mass m fixed at a distance r from its

centre. Find the minimum and maximum velocities which the coin can roll along the

table.

- Relevant Equations
- Conservation of energy: the difference in kinetic energy when the point mass is at its highest point and when it is at its lowest is equal to the difference in gravitational potential energy.

$$\frac{1}{2}m_0v^2 - \frac{1}{2}m_1v^2 = 2mgr$$

I reasoned that at the coin's slowest velocity, the energy it has must just be enough for it to reach the highest potential configuration: when the point mass is directly above the centre of mass of the coin, and its GPE is ##mg(R+r)##. I used this to find the minimum velocity, but I can't think of a reason there would be a max velocity for the coin.