Current through three closed loops.

[Moataz]

Homework Statement

Suppose you have three closed loops (ring-like) Each one has current going through it. They are set parallel to each other and the same distance away from each from each other. Suppose also the current through the one in the middle loop and the one on the right loop move counterclockwise if we looked at the loops from the right side. However, the left lopp's current is opposite to the other rings (clockwise as seen from the right side too) The question is what is going to happen to the previous configuration? Is any of the loops going to rotate if we supposed that their centers are stationary?

Homework Equations

I know F=IVxB

The Attempt at a Solution

I tried applying the formula, but the force direction I get is always perpendicular to the rings (no tangential force) which means no rotation will occur but the answer says that the left ring (the one with opposite current direction) will rotate?!

Homework Statement

Homework Equations

The Attempt at a Solution

 

[jbsteele]

The force due to the current in each loop will cause a torque on the loop, which will cause it to rotate. The left loop will experience a clockwise torque due to the current in the middle and right loops, while the other two loops will experience an equal and opposite counterclockwise torque. Therefore, the left loop will rotate, while the other two remain stationary.