Physics
(a) Which of the two, alternating current or direct current, produces a varying magnetic field when it flows through a conductor?
(b) State the frequency of the alternating current supply in India
Answer
(a) Alternating current produces a varying magnetic field when it flows through a conductor because alternating current changes its magnitude as well as direction periodically and thus, it provides a varying current and hence varying magnetic field as magnetic field is directly proportional to the applied current.
(b) 50 Hz.
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