Question

A 20-cm long conducting wire of 5-g carrying 5-A current is placed in a uniform magnetic field. The strength and direction of the magnetic field needed to levitate the wire are

Answer 1

My brain is failing me now, but remember that\[f = Bil \sin(\theta)\]and f > mg in order for it to levitate, I'd take the first the magnetic field entering the plane, and then solving for B. But there must be a better way of doing this, I am sure. I am sorry I can't give a more complete answer. Try posting on the Physics section :-)

Answer 2

thanks it's helpful i will try to solve it again now

Answer 3

No problem. Maybe with the right hand rule you can get a sign of the magnetic field. I would assume we want the +1 theta.

Answer 4

yes with right hand rule, thanks