A uniform magnetic field of induction `B` is confined to a cyclindrical region of radius `R`. The magnetic field is increasing at a constant rate of `dB//dt` (tesla`//` second). A charge `q` of mass `m`, placed at the point `P` on the periphery of the fixed experiences an acceleration :

Options

A. `(1)/(2)(eR)/(m)(dB)/(dt)` towards left
B. `(1)/(2) (eR)/(m)(dB)/(dt)` towards right
C. `(eR)/(m) (dB)/(dt)` towards left
D. zero

Answer

A

Explanation

`int vec(E).d vec(l) = (d phi)/(d t) = A(d B)/(d t)`
`vec(a) = -(q vec(E))/(m)`. Direction of induced field can determined from Lenz's law