(a) Derive the expression for the torque acting on a current-carrying loop placed in a magnetic field.
(b) Explain the significance of a radial magnetic field when a current-carrying coil is kept in it.

Answers (1)
S safeer

Let us consider a loop ABCD in a uniform magnetic field of strength B. and Let the current through the loop be I.

Consider force F_{1} on arm AB and force F_{2} on arm CD.

F_{1}=F_{2}=IbB

The net torque is given by -

\tau = I\: \frac{a}{2}\: b\: B\: +I\: \frac{a}{2}\: b\: B\:

\tau = IAB

Where A is the area of the loop

Now,

The magnetic moment of the loop.

\vec{m}=I\vec{A}

Therefore

\tau = mB

This is the expression for the torque acting on a current-carrying loop placed in a magnetic field.

(b) In a radial magnetic field, two sides of the rectangular coil remain perpendicular and other two ides remain parallel to magnetic field lines in all position of the coil.

Preparation Products

JEE Main Rank Booster 2021

This course will help student to be better prepared and study in the right direction for JEE Main..

₹ 13999/- ₹ 9999/-
Buy Now
Rank Booster NEET 2021

This course will help student to be better prepared and study in the right direction for NEET..

₹ 13999/- ₹ 9999/-
Buy Now
Knockout JEE Main April 2021 (Subscription)

An exhaustive E-learning program for the complete preparation of JEE Main..

₹ 4999/-
Buy Now
Knockout NEET May 2021

An exhaustive E-learning program for the complete preparation of NEET..

₹ 22999/- ₹ 14999/-
Buy Now
Knockout NEET May 2022

An exhaustive E-learning program for the complete preparation of NEET..

₹ 34999/- ₹ 24999/-
Buy Now
Exams
Articles
Questions