A circular loop of flexible iron wire has an initial circumference of 168 , but its circumference is decreasing at a constant rate of 11.0 due to a...

A circular loop of flexible iron wire has an initial circumference of 168 , but its circumference is decreasing at a constant rate of 11.0 due to a tangential pull on the wire. The loop is in a constant uniform magnetic field of magnitude 0.700 , which is oriented perpendicular to the plane of the loop. Assume that you are facing the loop and that the magnetic field points into the loop.