Q.
A bar magnet of magnetic moment 2.0 J/T lies aligned with the direction of uniform magnetic field of 0.25 T. What is the amount of work required to turn the magnet so as to align its magnetic moment normal to the field direction ?
see full answer
Start JEE / NEET / Foundation preparation at rupees 99/day !!
21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!
An Intiative by Sri Chaitanya
a
0.5 J
b
1.0 J
c
1.5 J
d
2.0 J
answer is A.
(Unlock A.I Detailed Solution for FREE)
Ready to Test Your Skills?
Check your Performance Today with our Free Mock Test used by Toppers!
Take Free Test
Detailed Solution
We know that potential energy of a bar magnet with its magnetic moment M inclined at an angle O with magnetic field B isU=−MBcosθ∴U0=−MBcos0=−MBU90=−MBcos90=0So, work done=U90−U0=0−(−MB)=MB=2⋅0×0⋅25=0⋅5J
Watch 3-min video & get full concept clarity