Question
Discuss induced emf produced in a conducting rod during its motion in direction perpendicular to uniform magnetic field with reference to Lorentz force and obtain its expression.
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Answer
Force acting on free electron is $\overrightarrow{ F }=-e(\vec{v} \times \overrightarrow{ B })$. Due to this force, free electron tend to meet at end Q and same amount of positive charge gets exposed at end $P$. Potential difference arising between P and Q has value $B vl$. Thus, it acts like a battery having emf $\varepsilon= Bvl$.
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