Question

The pole is pieces of a horse-shoe magnet are made cylindrical so that the deflection of the coil is proportional to

• A. the current flowing in the coil
• B. $\frac{1}{\text{current flowing in the coil}}$
• C. the magnetic field
• D. the square of current flowing in the coil

Answer 1

Answer: (A)

the current flowing in the coil

We know that for a galvanometer coil, $I=K\tan \theta$

where K is the reduction factor of the galvanometer and $\theta$ is the deflection.

So, $\theta \propto I$ .