A circular copper ring of radius r translates in its plane with a constant velocity v. A uniform magnetic field B exists in the space in a direction perpendicular of the plane o the ring. Consider different pairs of diametrically opposite points on the ring. (a) Between which pair of points is the emf? (b) Between which pair of points is the emf minimum? What is the value of this minimum emf?

Explanation

To solve the problem, we need to analyze the situation of a circular copper ring moving in a uniform magnetic field. The key points to consider are the induced electromotive force (emf) between different pairs of diametrically opposite points on the ring.

### Step-by-Step Solution:

1. **Understanding the Setup**:
- We have a circular copper ring of radius \( r \) that is translating in its plane with a constant velocity \( v \).
- A uniform magnetic field \( B \) is present, directed perpendicular to the plane of the ring.

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