Physics
Assertion (A): A transformer can increase the voltage of an alternating e.m.f.
Reason (R): This is achieved by keeping the number of turns in the secondary coil less than the number of turns in the primary coil.
- 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.
Answer
assertion is true but reason is false.
Explanation
Assertion (A) is true. A transformer can increase the voltage of an alternating electromotive force (e.m.f.). This is accomplished through electromagnetic induction, where a changing magnetic field in the primary coil induces a voltage in the secondary coil.
Reason (R) is false. To increase the voltage in the secondary coil, the number of turns in the secondary coil must be greater than the number of turns in the primary coil, not less. This allows for a step-up transformation of voltage.
Related Questions
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Reason (R): The specific heat capacity of a substance is not its characteristic property.
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Reason (R): The lamination of core prevents the loss of energy due to induced currents in the core.
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