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प्रश्न
Consider the following statements:-
(A) An emf can be induced by moving a conductor in a magnetic field.
(B) An emf can be induced by changing the magnetic field.
विकल्प
Both A and B are true
A is true but B is false
B is true but A is false
Both A and B are false
उत्तर
Both A and B are true
Statement A is true, as an emf can be induced by moving a conductor with some velocity v in a magnetic field B. It is given by
`e=Bvl`
Statement B is true, as an emf can be induced by changing the magnetic field that causes the change in flux ϕ through a conductor or a loop. It is given by
`e=-(dphi)/(dt)`
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