A small coil `C` with N = 200 turns is mounted on one end of a balance beam and introduced between the poles of an electromagnet as shown in Fig. The cross sectinal area of the coil is `S = 1.0 cm^(2)`, the length of the arm `OA` of the balance beam is `l = 30 cm`. When there is no current in the coil the balance is irl equilibrium. On passing a current `I = 22 mA` through the coil the equiibrium is restroed by putting the additional counterweight of mass `Delta m = 60 mg` ont he balnace pan. Find the magnetic induction at the spot where the coil is located.

Answer

`[(Mgl_(2))/(INA)]`