A wire moves with some speed perpendicular to a magnetic field. Why is emf induced across the rod?

Explanation

To understand why an electromotive force (emf) is induced across a wire moving perpendicular to a magnetic field, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding the Setup**:
- We have a wire of length \( L \) moving with speed \( V \) perpendicular to a magnetic field \( B \). The magnetic field is directed downwards.

2. **Direction of Motion and Magnetic Field**:
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