A wheel with 10 spokes each of length L m is rotated with a uniform angular velocity `omega` in a plane normal ti the magnetic field B. The emf induced between the axle and the rim of the wheel

Options

A. `(1)/(2)NomegaBL^(2)`
B. `(1)/(2)NomegaBL^(2)`
C. `omegabL^(2)`
D. `NomegaBL^(2)`

Answer

b

Explanation

Cosider a single poke in the wheel as shown in the figure
Motional emf developed in the small element dl
`depsilon = Bvdl`
`epsilon= intdepsilon = intBomegaldl= Bomegaintldl= (1)/(2)BomegaL^(2)`