Neco 2017 Physics Question 42

A rectangular coil has 30 turns, each side \(0.20\ \text{m}\) by \(0.10\ \text{m}\), and rotates at a constant angular speed of \(300\ \text{rad s}^{-1}\) in a uniform magnetic field of \(0.5\ \text{T}\). The axis of rotation is perpendicular to the field and passes through the centre of the coil. The coil's resistance is \(2\ \Omega\). (a) Find the maximum emf induced in the coil. (b) If the coil is connected to an external resistor of \(8\ \Omega\), determine the maximum current and the average power delivered to the resistor over one complete rotation. (c) Suppose the coil is instead rotated at half the angular speed while the number of turns is doubled, with the same magnetic field and resistances. Which configuration yields a greater average power to the resistor? Justify your answer.