Physics-
General
Easy
Question
A small coil C with N=200 turns is mounted on one of a balance beam and introduced between the poles of an electro magnet as shown in fig. The cross-sectional area of the coil is 
, 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 in equilibrium. On passing a current I=22 mA through the coil the equilibrium is restored by putting the additional counterweight of mass 
on the balance pan. Find the magnetic induction at the spot where the coil is located.
- 0.3 T
- 0.1 T
- 0.4 T
- 0.9 T
The correct answer is: 0.4 T
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