" A circular loop of wire 10 cm in diameter is placed with its normal making an angle of 30 degrees with the direction of a uniform 0.50T magnetic field. The loop is "wobbled" so that its normal rotates in a cone about the field direction at the constant rate of 100rev/min; the angle between the normal and the field direction (= 30 degrees) remains unchanged during the process. What emf appears in the loop?" Alright I know that I am supposed to use the equation: E(potential difference) = BDv With B as the magnetic field, D as the area with a magnetic field that is not equal to 0 and v is the velocity. The back of the book says that the emf is zero. Is this because the loop is not being displaced ( it is wobbling in the same spot?) so it's velocity is zero?