A solid sphere, a hollow sphere and a ring are released from top of an inclined plane (frictionless) so that they slide down the plane. Then maximum acceleration down the plane is for (no rolling)

A particle of mass $$m$$ moves along line PC with velocity $$v$$ as shown. What is the angular momentum of the particle about P?

If suddenly the gravitational force of attraction between Earth and a satellite revolving around it becomes zero, then the satellite will

Energy required to move a body of mass $$m$$ from an orbit of radius $$2R$$ to $$3R$$ is