A hot-wire ammeter indicates 5 A when the current through it is i = I₀ sin²ωt. Assuming the instrument responds to the heating effect, determine I₀.
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A hot-wire ammeter indicates 5 A when the current through it is i = I₀ sin²ωt. Assuming the instrument responds to the heating effect, determine I₀.

G1 Physics · Accepted Answer

A hot-wire instrument measures RMS current. For i = I₀ sin²ωt, Iᵣₘₛ = I₀√(3/8). Therefore, 5 = I₀√(3/8), which gives I₀ = 10√(2/3) A.