Question 1

State Biot-Savart law in vector form.

Accepted Answer

The Biot-Savart law in vector form expresses the magnetic field $d\mathbf{B}$ at a point due to a current-element $Id\mathbf{l}$ at a distance $\mathbf{r}$. Mathematically, it is written as $d\mathbf{B} = \frac{\mu0}{4\pi} \frac{I(d\mathbf{l} 	imes \mathbf{r})}{r^3}$, where $\mu0$ is the permeabili

Question 2

State Ampere's circuital law.

Accepted Answer

Ampere's circuital law states that the line integral of the magnetic field $\mathbf{B}$ around any closed loop is equal to $\mu0$ times the total current $I$ enclosed by that loop. Mathematically, it is expressed as $\oint \mathbf{B} \cdot d\mathbf{l} = \mu0 I$. This law is extremely useful for calc

Question 3

What is the radius of the circular path of a charged particle in a perpendicular magnetic field?

Accepted Answer

When a charged particle of mass $m$ and charge $q$ enters a uniform magnetic field $B$ perpendicularly with velocity $v$, it follows a circular path. The magnetic force provides the necessary centripetal force. Equating $qvB = \frac{mv^2}{r}$, the radius $r$ of the circular path is derived as $r = \

Question 4

What is the basic principle of a moving coil galvanometer?

Accepted Answer

The basic principle of a moving coil galvanometer is that a current-carrying coil placed in a uniform magnetic field experiences a deflecting torque. The magnitude of this magnetic torque is given by $	au = NIAB \sin	heta$, where $N$ is the number of turns, $I$ is the current, $A$ is the area of t

Question 5

How can a galvanometer be converted into an ammeter?

Accepted Answer

A galvanometer can be converted into an ammeter by connecting a very low resistance, known as a shunt resistance, in parallel with the galvanometer coil. This low resistance ensures that most of the main circuit current passes through the shunt, protecting the delicate galvanometer mechanism from da

Moving Charges and Magnetism