MCQ
When a $‘J’$ shaped conducting rod is rotating in its own plane with constant angular velocity $w$, about one of its end $P$, in a uniform magnetic field $\vec B\,$ directed normally into the plane of paper) then magnitude of emf induced across it will be
  • A
    $B\omega\, \sqrt {{L^2} + {{\text{l}}^2}} $
  • B
    $\frac{1}{2}B\omega {L^2}$
  • $\frac{1}{2}B\omega ({L^2} + {{\text{l}}^2})$
  • D
    $\frac{1}{2}B\omega {{\text{l}}^2}$

Answer

Correct option: C.
$\frac{1}{2}B\omega ({L^2} + {{\text{l}}^2})$
c
$e=\frac{1}{2} B \omega(\sqrt{l^{2}+L^{2}})^{2}$

$e=\frac{1}{2} B \omega\left(l^{2}+L^{2}\right)$

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