A student is testing a model wind turbine generator in a physics laboratory. The generator contains a flat, circular coil consisting of 650 turns that rotates at a constant rate within a uniform magnetic field. As the coil spins, an alternating current is induced.
The graphs below show the relationship between the magnetic flux linkage (λ\lambdaλ) and the induced e.m.f. (ε\varepsilonε) of the rotating coil over one full rotation period TTT.
When the turbine is spinning steadily at 40 revolutions per second40\text{ revolutions per second}40 revolutions per second, the maximum induced e.m.f. V0 V_0\,V0 measured across the coil is 8.2 V.
With reference to Faraday’s law of electromagnetic induction, explain why the induced e.m.f. is zero at the instant when the magnetic flux linking the coil is at its maximum.
Calculate the maximum magnetic flux through a single turn of the coil using the equation: V0=2π×f×(maximum magnetic flux linkage)V_0 = 2\pi \times f \times (\text{maximum magnetic flux linkage})V0=2π×f×(maximum magnetic flux linkage) Give a suitable unit with your answer.