Question

A rod of length 'L' is moving as shown what will be the EMF induced.?

Answer 1

ε = BLv

Answer 2

Explanation:
When a rod of length $L$ moves with speed $v$ in a magnetic field $B$, free charges in it experience the Lorentz force $\vec{F} = q\,(\vec{v}\times\vec{B})$. For the given directions (with the result $V_a > V_b$), the induced potential difference across its ends is

$$\varepsilon = V_a - V_b = B\,L\,v.$$

Answer:

$$\varepsilon = B\,L\,v$$