A square aluminium plate of side 10 cm is placed normal to a spatially uniform…
PHYSICS · Subjective · A Level · Physics · Fields and their consequences · Fields and their consequences
Problem
A square aluminium plate of side 10 cm is placed normal to a spatially uniform magnetic field whose magnitude varies sinusoidally with constant amplitude Bm=0.08T. The frequency of variation can be adjusted.
(a) Find the rms emf induced around the edge of the plate when the frequency is 5 kHz.
(b) The frequency is then raised to 50 kHz while keeping Bm unchanged. Calculate the new rms emf.
(c) The electrical resistance offered to the circulating current around the perimeter of the plate is 0.02Ω. Compare the average rates of heat production in the two cases and comment on your result.