A metal disk of radius a rotates with a constant angular velocty `omega` about its axis. The potential difference between the centre and the rim of the disc is (m=mass of electron, e=charge on electron)

Options

A. zero
B. `(m_(0)omega^(2) R^(2))/(2e)`
C. `(m_(0)omegaR^(3))/(3e)`
D. `(em_(0)omegaR^(2))/2`

Answer

B

Explanation

`eE=m_(0)omega^(2)r `
`rArr intEdr=(m_(0)omega^(2))/e int_(0)^(R) dr`
`rArr V=(m_(0)omega^(2) R^(2))/(2e)`