Question
A hollow smooth uniform sphere $$A$$ of mass $$m$$ rolls without sliding on a smooth horizontal surface. It collides head on elastically with another stationary smooth solid sphere $$B$$ of the same mass m and same radius. The ratio of kinetic energy of $$B$$ to that of $$A$$ just after the collision is
A hollow smooth uniform sphere $$A$$ of mass $$m$$ rolls without sliding on a smooth horizontal surface. It collides head on elastically with another stationary smooth solid sphere $$B$$ of the same mass m and same radius. The ratio of kinetic energy of $$B$$ to that of $$A$$ just after the collision is
A.
$$1:1$$
B.
$$2:3$$
C.
$$3:2$$
D.
None of these
Answer :
$$3:2$$
Solution :
After collision velocity of $$COM$$ of $$A$$ becomes zero and that of $$B$$ becomes equal to initial velocity of $$COM$$ of $$A.$$ But angular velocity of $$A$$ remains unchanged as the two spheres are smooth.
After collision velocity of $$COM$$ of $$A$$ becomes zero and that of $$B$$ becomes equal to initial velocity of $$COM$$ of $$A.$$ But angular velocity of $$A$$ remains unchanged as the two spheres are smooth.
