Question

Ball a of mass m, after sliding from an inclined plane, strikes elastically another ball b of same mass at rest. Find the minimum height h so that ball b just completes the circular motion of the surface at

c.(all surfaces are smooth.)

Answer 1

mgh=1/2 mv^2 + 2mgR

gh= v^2÷2 + 2gR

Required velocity at the top ,v=√(gR)

gh = gR/2 + 2 gR

h=5/2 R