1. Tardigrade
  2. Question
  3. Physics
  4. A bar magnet having a magnetic moment of 2.0 × 105 JT -1, is placed along the direction of uniform magnetic field of magnitude B =14 × 10-5 T. The work done in rotating the magnet slowly through 60° from the direction of field is :

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A bar magnet having a magnetic moment of $2.0 \times 10^{5} \,JT ^{-1}$, is placed along the direction of uniform magnetic field of magnitude $B =14 \times 10^{-5} T$. The work done in rotating the magnet slowly through $60^{\circ}$ from the direction of field is :

JEE MainJEE Main 2022Magnetism and Matter

Solution:

Work done $= MB \left(\cos \theta_{1}-\cos \theta_{2}\right)$
$\theta_{1}=0^{\circ}, \theta_{2}=60^{\circ} $
$=2 \times 10^{5} \times 14 \times 10^{-5}(1-1 / 2) $
$=14 \,J$