A `U`-shaped wire of mass `m` and length `l` is immersed with its two ends in mercury (see figure).T
Channel: Doubtnut
Date: 26/01/2020

A `U`-shaped wire of mass `m` and length `l` is immersed with its two ends in mercury (see figure).The wire is in a homogeneous field of magnetic induction `B`.If a charge, that is a current pulse `q=int idt`, is sent through the wire, the wire will jump up.The amount of charge the wire reaches a hight is `Nsqrt15C` assuming that the time of the current pulse is very small in comparionson with the time of flight.Make use of the fact that impulse of force equals `int F dt` which equals `mv`.`B=01(Wb)/m^(2),m=10gm,l=20cm&h=3meters`.Then find the value of `N`.