Embibe Experts Solutions for Chapter: Electromagnetism, Exercise 1: West Bengal Board-2018

A current-carrying loop behaves as a magnetic dipole. Explain.

Find out the expression for the magnetic field at a point on the axis of a toroid of $\mathrm{N}$ turns having an average radius $\mathrm{r}$ and carrying a current $\mathrm{I}$. Show that the magnetic field at the open space inside and outside the toroid is zero.

Two long parallel straight wire $P and Q$ separated by a distance $5 \mathrm{cm}$ in air carry a current of $4\mathrm{A} \mathrm{and} 2\mathrm{A}$respectively in

 the same direction. Find the force acting per cm of wire and indicate the direction of force.

A copper wire of length $\mathrm{L}$is bent to form a circular loop. If $\mathrm{i}$ current flows through the loop, find out the magnitude of the magnetic moment of the loop.

Write down the Bio-Savart Law. Show its vector form.

Derive an expression for torque on the rectangular coil of area $\mathrm{A}$ carrying a current $\mathrm{I}$ and placed in a uniform magnetic field $\mathrm{B}$. Indicate the direction of the torque on the loop.

Define the electromagnetic unit of current.