The torque on a rectangular coil placed in a uniform magnetic field is large when the

The torque (τ) acting on a rectangular coil in a uniform magnetic field is given by the formula τ = NIAB sin θ, where N is the number of turns, I is the current, A is the area of the coil, B is the magnetic field strength, and θ is the angle between the magnetic field and the normal to the coil's plane. According to this relationship, the torque is directly proportional to the number of turns (N). Therefore, a larger number of turns results in a larger torque. Conversely, if the plane of the coil is perpendicular to the magnetic field, the angle θ between the normal and the field is 0°, making sin θ = 0, which results in zero torque. Similarly, a smaller area (A) would decrease the torque rather than increase it. Thus, increasing the number of turns is the correct factor for a large torque.