A certain elastic conducting material is stretched into a circular loop of 12.0 cm radius. It is placed with its plane perpendicular to a uniform 0.800 T magnetic field. When released, the radius of the loop starts to shrink at an instantaneous rate of 75.0 emfs. What emf is induced in the loop at that instant?

Explanation

To solve the problem of finding the induced EMF in the circular loop, we will follow these steps:

### Step 1: Understand the given values
- Radius of the loop (r) = 12.0 cm = 0.12 m (conversion to meters)
- Magnetic field (B) = 0.800 T
- Rate of change of radius (dr/dt) = -75.0 cm/s = -0.75 m/s (negative because the radius is shrinking)

### Step 2: Calculate the area of the loop
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