A He nucleus makes a full rotation in a circle of radius 0.8 meter in 2 sec. The value of the mag. field B at the centre of the circle will be ................... Tesla.
Options:
(a) `10^(-19)/mu_o`
(b) `10^(-19)mu_o`
(c) `2xx10^(-10)mu_o`
(d) `(2xx10^(-10))/mu_o`