Final answer:
Induced emf is described by Faraday's law of induction, directly proportional to the rate of magnetic flux change. The change in flux and the number of turns in the coil are used to calculate the average induced emf over a time interval.
Step-by-step explanation:
Understanding Induced Electromotive Force (emf)
The question pertains to the concept of induced emf and its calculation using Faraday's law of electromagnetic induction. Induced emf is created when there is a change in the magnetic flux linked with a circuit. Faraday's law states that this induced emf is directly proportional to the rate of change of the magnetic flux through the circuit and inversely proportional to the time over which this change occurs.
The formula for calculating the average induced emf over a time interval Δt is given by the equation:
Ε = -N (ΔΦ / Δt)
Where Ε is the induced emf, N is the number of turns in the coil, ΔΦ is the change in magnetic flux, and Δt is the time interval. For example, if a 1000-turn coil with a diameter of 20.0 cm is rotated in the Earth's magnetic field and aligns from perpendicular to parallel in 10.0 ms, we must compute the change in magnetic flux ΔΦ to find the average emf induced during this interval.