Figure shows a mass m placed on a frictionless horizontal table and attached toa string passing through a mall hole in the surface. Initially, themas movesin a circle of radius `r_0` with a speed `v_0` and the ree end of the string is held by a person. The person pulls on the string slowly to decrease the radius of th circle of r. a. Find the tension in the string when the mass moves in the circle of radius r. b. Calculate the chasnge in the kinetic energy of the mass

Explanation

To solve the problem step by step, we will address both parts of the question: finding the tension in the string when the mass moves in a circle of radius \( r \) and calculating the change in kinetic energy of the mass.

### Step-by-Step Solution

**Part A: Finding the Tension in the String**

1. **Understanding the System**:
- A mass \( m \) is moving in a circle of radius \( r \) with speed \( v \).
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