JEE Main · 2022 · 25 Jul 2022 · Shift 2 · Electromagnetic Induction

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When you walk through a metal detector carrying a metal object in your pocket, it raises an alarm. This phenomenon works on

(A)Electromagnetic induction
(B)Resonance in ac circuits✓ Correct
(C)Mutual induction in ac circuits
(D)interference of electromagnetic waves

Answer: (B)

Solution

A metal detector works by transmitting an electromagnetic signal and analyzing the return signal from the target. The presence of metal changes the resonance characteristics of the AC circuit in the detector, which triggers the alarm. Therefore, it operates on the principle of resonance in AC circuits.

JEE Main · 2022 · 25 Jul 2022 · Shift 2 · Single correct option

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