A circular disc of radius 20 cm is rotating with a constant angular speed of `2.0 rad//s` in a uniform magnetic field of 0.2 T. Find the e.m.f. induced between the centre and rim of the disc. Given magnetic field is along the axis of rotation of disc.

Explanation

Here, `r = 20 cm = (1)/(5) m`
`omega = 2.0 rad//s, B = 0.2 T, e = ?`
`e = (1)/(2) B omega r^(2) = (1)/(2) xx 0.2 xx 0.2 xx ((1)/(5))^(2)`
`= 8 xx 10^(-3) V = 8 mV`