Physics
Assertion (A) : When current is passed through a wire, a magnetic field is generated around the wire.
Reason(R) : Whenever there is a change of magnetic flux linked up with the coil, the induced current is generated in the coil.
- Both A and R are correct, and R is the correct explanation of A.
- Both A and R are correct, but R is not the correct explanation of A.
- A is correct but R is wrong.
- Both A and R are wrong.
Answer
Both A and R are correct, but R is not the correct explanation of A
Explanation :
Assertion (A) is true: According to Oersted’s experiment and Ampere’s law, passing an electric current through a conductor generates concentric circular magnetic field lines around it.
Reason (R) is true: According to Faraday’s law of electromagnetic induction, A changing magnetic flux through a coil induces an electromotive force, hence a current.
Reason (R) describes electromagnetic induction (how a changing magnetic field induces current in a coil). Assertion (A) describes the generation of a magnetic field by a steady current. These are two distinct phenomenon, one is about field creation, the other about induced currents, so the Reason (R) does not explain the Assertion (A).
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