A metallic rod of length ‘l’ is rotated with a frequency ‘v’, with one end hinged at the centre and the other end at the circumference of a circular metallic ring, about an axis passing through the centre and perpendicular to the plane of the ring. A constant and uniform magnetic field B parallel to the axis is present everywhere.
- Obtain the expression for the emf induced between the centre and the ring.
- Given that the rod has resistance ‘R’, then how much power will be generated?
CBSE OUTSIDE DELHI - SET 3 GUHAWATI 2015
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- Emf induced $\int^{1}_{0}\text{Bwrdr}$
$\because \omega = 2\pi\text{v}$
$\therefore\varepsilon = \pi\text{Bvl}^{2}$
- $\text{P} = \frac{\varepsilon^2}{\text{R}} = \frac{(\pi\text{Bvl}^{2})^{2}}{\text{R}}$
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