Physics
Assertion (A): A transformer cannot be used with a direct current.
Reason (R): The lamination of core prevents the loss of energy due to induced currents in the core.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true and R is not the correct explanation of A.
- assertion is false but reason is true.
- assertion is true but reason is false.
Electro-Magnetism
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Answer
Both A and R are true and R is the correct explanation of A.
Explanation
Assertion (A) is true. A transformer cannot be used with direct current (DC) because it relies on the principle of electromagnetic induction, which requires a changing magnetic field. In DC, the current flows in one direction without changing, so there is no alternating magnetic field to induce voltage in the secondary coil of the transformer.
Reason (R) is true. The lamination of the core in a transformer is used to prevent energy loss due to induced currents in the core, known as eddy currents. By laminating the core, the magnetic flux is confined to the individual lamination, reducing the eddy current losses
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