Use the Figure to the Right to Answer the Next

question 54

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.

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Definitions:

Gallon

A unit of volume for liquid measure in the United States, equal to 3.785 liters.

Gas

A state of matter characterized by high compressibility and expansion to fill any container, often used as a fuel.

Twenty-Dollar Bill

Currency note of the United States valued at twenty dollars, featuring the portrait of President Andrew Jackson.

Empty

Lacking content, occupants, or value; not filled or occupied.