As the current loop in Figure 28.10 rotates over the first \(90^{\circ}\), do the magnitudes of 

(a) the magnetic force exerted on the horizontal sides and 

(b) the torque caused by these forces increase, decrease, or stay the same?

(c) As the loop rotates, do the two vertical sides experience any force, and, if so, do these forces cause any torque?

(d) What happens to the torque as the loop rotates beyond \(90^{\circ}\) ?

Figure 28.10 Magnetic forces exerted on a square current loop that is oriented so that its magnetic dipole moment is perpendicular to an external magnetic field. Force exerted by magnetic field on top and bottom sides of current-carrying loop... B TE ...creates torque that tends to rotate loop. FB