Question

Faraday's Law III

The armature of a small generator consists of a flat, square coil with N turns and sides with length L. The coil rotates in a magnetic field of magnitude B with a constant angular speed ω.  

a) Write an expression for the flux ΦB(t) through the coil as a function of time. Assume the plane of the coil is perpendicular to the magnetic field at time t=0. (Your answer should be in terms of ω, N, B and L.)

b) Write an expression for the magnitude of the induced emf ε(t) in the coil as a function of time. (Your answer should be in terms of ω, N, B and L.)

c) In one example, the coil has 200 turns, sides with a length of 1.85 cm and rotates in a magnetic field of 8.10×10⁻² T . What is the angular speed of the coil if the maximum emf produced is 2.00×10⁻² V?

Answer 1