How many times per full revolution does the direction of emf induced in a rotating coil reverse?
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How many times per full revolution does the direction of emf induced in a rotating coil reverse?

G1 Physics · Accepted Answer

Step 1: One rotation of a coil through 2π radians changes Φ = NBAcosθ through one full sinusoidal period. Step 2: Induced emf ε = NBAωsinθ completes one cycle each revolution, with positive and negative half-cycles. Step 3: It reverses sign twice per full revolution; answer B. Final answer: (B) twice per revolution.