You move a ball of mass m away form a sphere of mass M. (a) Does the gravitational patential energy of the systemof ball and sphere increase or decrease ? (b) Is positive work or negative work done by the gravitational force between the ball and the sphere ?

Explanation

To solve the problem step by step, we will analyze the gravitational potential energy and the work done by the gravitational force when moving a ball of mass \( m \) away from a sphere of mass \( M \).

### Step 1: Understanding Gravitational Potential Energy
The gravitational potential energy \( U \) between two masses \( m \) and \( M \) separated by a distance \( r \) is given by the formula:
\[ U = -\frac{G m M}{r} \]
where \( G \) is the gravitational constant.
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