An elastic conducting material is stretched into a circular loop of 11.0 cm radius. It is placed with its plane perpendicular to a uniform 0.900 T magnetic field. When released, the radius of the loop starts to shrink at an instantaneous rate of 80.0 cm/s. What emf is induced in the loop at that instant? I used: EMF = - d(change in mag flux)/dt EMF = - (.900)(.11)^2*PI*5.027 rad/sec = -.17198, i also tried the positive version of that, both wrong. Any ideas why? Thanks.