Find the mismatch pair
- Induction furnace : eddy current
- A.C generator : armature coil
- LCR circuit : resonance
- Transformer : D.C. voltage
- Magnetic brakes : magnetic flux
The Correct Option is D
Approach Solution - 1
A transformer operates based on the principle of electromagnetic induction and is designed to work with alternating current (AC). It cannot work with direct current (DC) because a DC supply does not produce the varying magnetic flux needed for the operation of the transformer.
Therefore, the correct mismatch pair is Transformer : D.C. voltage, as a transformer is not used for DC voltage.
The correct option is (D) : Transformer : D.C. voltage
Approach Solution -2
Correct Matches:
Induction furnace → uses eddy currents for heating metals. ✔️
A.C generator → has an armature coil where emf is induced. ✔️
LCR circuit → shows resonance at a specific frequency. ✔️
Magnetic brakes → work based on changing magnetic flux causing eddy currents. ✔️
Mismatch:
Transformer → works on A.C. voltage, not D.C. voltage.
Transformers require a changing magnetic field (which D.C. cannot produce) for mutual induction.
Final Answer: Transformer : D.C. voltage ❌
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