An annular circular brass disk of inner radius `'r'` and outer radius `'R'` is rotating about an axis passing through its centre and perpendicular to its plane with a uniform angular velocity `'omega'` in a uniform magnetic filed of induction `'B'` normal to the plane of the disk. The induced emf between the inner and outer edge of the annular disk is

Options

A. `(B omega(r^2+R^2))/(2)`
B. `(B omega(R^2-r^2))/(2)`
C. `(B omega(r-R))/2`
D. `(B omega(r+R))/(2)`

Answer

B