Question

Find the mismatch pair

• A. Induction furnace : eddy current
• B. A.C generator : armature coil
• C. LCR circuit : resonance
• D. Transformer : D.C. voltage
• E. Magnetic brakes : magnetic flux

Answer 1

The Correct Option is D

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

Answer 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 ❌