A frog of mass m jumps from the edge of a plank of mass M of length L to the other edge. The plank is on water and is free to move, assume no friction whatsoever. What is the minimum value of the speed of the frog ?
Conservation of momentum and energy
Some kinematics equations
The answer given is sqrt((MgL)/(m+M))
The Attempt at a Solution
I think that the minimum speed means the magnitude of the velocity at the highest point, meaning Vx. But I cannot find [/B]