Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • School
  • Define the dipole moment of a magnetic dipole. Write its SI unit. Obtain the expression for the torque acting on a magnetic dipole placed in an external uniform magnetic field.  

Define the dipole moment of a magnetic dipole. Write its SI unit.

Obtain the expression for the torque acting on a magnetic dipole placed in an external uniform magnetic field.

 

 

Answers (1)

Magnetic dipole moment -  Magnetic dipole means magnetic south pole and north pole separated by a small distance. The magnetic dipole moment is the product of poles of magnet and distance between them or it is the product of the current flowing through coil and area.

It's SI unit is Am2.

Torque

consider the rectangular loop ABCD  with current I ampere flowing and having the number of turns N. The force acting on arm AD and BC is zero and the force is acted only on the arm AB and CD.

The arm AB exert a force F_{1} and arm CD exert a force F_{2} 

F_{1}= IbB 

F_{2}= IbB   

\left | F_{1} \right |=\left | F_{2} \right | and the directions are opposite.

Therefore, the net force is zero. But it will experience a net torque.

We know that Torque = Force X Perpendicular distance between them

Therefore, \tau = F_{1}\frac{a}{2}+ F_{2}\frac{a}{2}= IbB\frac{a}{2}+ IbB \frac{a}{2} = I(ab)B

                    \tau = IAB

where A = ab is the area of the rectangle.

 the number turns are N then,  

\tau =N IAB

If the plane loop makes an angle with the magnetic field then the magnitude of torque become,

\tau=NIABsin\theta

Posted by

Safeer PP

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads

Similar Questions

Trending Articles/News

anam-khan

CBSE Board exams twice a year from 2025, no plan for semesters: MoE
anam-khan

CBSE Class 12 board exams 2025 to have 50% competency-based questions; no change in 10th
anam-khan

CBSE Class 12 board exams 2024 over; expected result date, trends of last 10 years

Latest Question