JEE Mains · Physics · STD 12 -7. Alternating current
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
- C Mutual induction in \(ac\) circuits
- D interference of electromagnetic waves
Answer & Solution
Correct Answer
(B) Resonance in \(ac\) circuits
Step-by-step Solution
Detailed explanation
Metal detector works on the principle of transmitting an electromagnetic signal and analyses a return signal from the target. So it works on the principle of resonance in \(AC\) circuit.
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