591(B) ?
Akash Anand Wrong answerUpvote·0· Reply ·2013-09-11 05:34:09
4 Answers
591
1133It will be (A)
since axis of rotation is in the x-y plane, therefore I = mr22
mr22α = (I0πr2 k ) x B(2i - 2j + 5k)
- Akash Anand Excellent ..keep it up
1161Key Concept: Net torque in a loop placed in a magnetic field will be cross product of it magnetic moment and magnetic field. And net force is zero. On the other hand in this case we have to find the direction of axis about which the ring is rotating. In this case that axis is in XY plane passing through origin so whatever the solution that Sourish is given is correct.