Use the Figure to the Right to Answer the Next

Multiple Choice

Use the figure to the right to answer the next problem. A ball of mass of mass m is tied with a light string to a vertical post of radius R_p and slides on a frictionless horizontal surface. As the ball travels around the post, the string wraps around the post, shortening the length. At t = 0 s, its speed is v_o and radius is r_o.

-As the string wraps around the post,which of the following statements is true?

A) Angular momentum is conserved but not the mechanical energy.
B) Angular momentum is not conserved but the mechanical energy is conserved.
C) Both the angular momentum and the mechanical energy are conserved.
D) Angular momentum increases as the string gets shorter.
E) Whether the angular momentum and mechanical energy are conserved depends on v_o and r_o.