A bar magnet having a magnetic moment of 2 x 10⁴JT⁻¹ is free to rotate in a horizontal

A Bar Magnet Having A Magnetic Moment Of 2 X Physics Question

A bar magnet having a magnetic moment of 2 x 10⁴JT⁻¹ is free to rotate in a horizontal plane. A horizontal magnetic field B = 6 x 10⁻⁴T exists in the space. The work done in taking the magnet slowly from a direction parallel to the field to a direction 60⁰ from the field is

Options

(a) 12 J
(b) 6 J
(c) 2 J
(d) 0.6 J

Correct Answer:

6 J

Explanation:

Work done
= MB (cos θ₁ – cos θ₂)
= MB (cos 0⁰ – cos 60⁰)
= MB (1 – 1/2) = 2 x 10⁴ x 6 x 10⁻⁴ /2 = 6 J

Related Questions:

  1. Three identical spherical shells, each of mass m and radius r are placed
  2. Electrons in a certain energy level n=n₁, can emit 3 spectral lines. When they
  3. When npn transistor is used as an amplifier
  4. One coolie takes 1 minute to raise a suitcase through a height of 2 m
  5. The excitation potential of hydrogen atom in the first excited state is

Topics: Magnetic Effects of Current and Magnetism (167)
Subject: Physics (2479)

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

NEETLab Mobile App

Share this page with your friends

Be the first to comment

Leave a Reply

Your email address will not be published.


*