A current loop in a magnetic field - Vidyadip

MCQ

A current loop in a magnetic field

A
experiences a torque whether the field is uniform or non uniform in all orientations.
B
can be in equilibrium in one orientation.
C
can be in equilibrium in two orientations,both the equilibrium states are unstable.
✓
can be in equilibrium in two orientations, one stable while the other is unstable.

✓

Answer

Correct option: D.

can be in equilibrium in two orientations, one stable while the other is unstable.

d
When a current loop is placed in a magnetic field it experiences a torque. It is given by

$\vec{\tau}=\vec{M} \times \vec{B}$

where, $\vec{M}$ is the magnetic moment of the loop and $\vec{B}$ is the magnetic field.

or $\quad \tau=M B \sin \theta$ where $\theta$ is angle between $M$ and $B$ When $\vec{M}$ and $\vec{B}$ are parallel (i.e. $\theta=0^{\circ}$ ) the equilibrium is stable and when they are antiparallel (i.e. $\theta=\pi$ ) the equilibrium is unstable.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

JEE STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

A stream-lined body falls through air from a height $h$ on the surface of liquid. Let $d$ and $D$ denote the densities of the materials of the body and the liquid respectively. If $D > d$, then the time after which the body will be instantaneously at rest, is

A particle moves in a plane along an elliptic path given by $\frac{x^2}{a^2}+\frac{y^2}{b^2}=1$. At point $(0, b)$, the $x$-component of velocity is $u$. The $y$-component of acceleration at this point is

Let $\gamma_1$ be the ratio of molar specific heat at constant pressure and molar specific heat at constant volume of a monoatomic gas and $\gamma_2$ be the similar ratio of diatomic gas. Considering the diatomic gas molecule as a rigid rotator, the ratio, $\frac{\gamma_1}{\gamma_2}$ is

$Assertion : $ Machine parts are jammed in winter.
$Reason :$ The viscosity of lubricant used in machine parts increase at low temperatures.

The relation between two specific heats of a gas is

A transparent cube of side $d$, made of a material of refractive index $\mu_2$, is immersed in a liquid of refractive index $\mu_1(\mu_1 < \mu_2)$. A ray is incident on the face $AB$ at an angle $\theta $ (shown in the figure). Total internal reflection takes place at point $E$ on the face $BC$. The $\theta$ must satisfy

Consider a situation in which a ring, a solid cylinder and a solid sphere roll down on the same inclined plane without slipping. Assume that they start rolling from rest and having identical diameter.

The correct statement for this situation is:-

Infinite rods of uniform mass density and length $L, L/2, L/4....$ are placed one upon another upto infinite as shown in figure. Find the $x-$ coordinate of centre of mass

A square coil ${10^{ - 2}}{\,m^2}$ area is placed perpendicular to a uniform magnetic field of intensity ${10^3}\,Wb/{m^2}$. The magnetic flux through the coil is........$weber$

A bar magnet of length $6\,cm$ has a magnetic moment of $4\,J\,T^{-1}$. Find the strength of magnetic field at a distance of $200\,cm$ from the centre of the magnet along its equatorial line.