# Homework Help: Current Loops in a Magnetic Field Problem Question.

1. Feb 6, 2005

### R0B0

Hi, I'm just wondering if anyone knows how I should be setting up my FBD for this question, or any hints as to how to go about doing this question:

"A long piece of wire with a mass of 0.100 kg and a total length of 4.00 m is used to make a square coil with a side of 0.100 m. The coil is hinged along a horizontal side, carries a 3.40 A current, and is placed in a vertical magnetic field with a magnitude of 0.0100T. Determine the angle that the plane of the coil makes with the vertical when the coil is in equilibrium. Find the torque acting on the coil due to the magnetic force at equilibrium".

I think I know how to do part b but I'm pretty sure that requires the angle from part A. I'm assuming you sum up your forces (FB and Gravity?) and solve for the angle but I'm just hung up on the fact that its hinged and I'm just having problems getting started.

Any help would be appreciated, thanks.

-Rob