Alternating Current

An alternating current is represented by the equation I = I∫sinπt which of the following equation represents an alternating current of frequency and amplitude twice that of the above current ?

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An alternating current is represented by the equation I = I∫sinπt which of the following equation represents an alternating current of frequency and amplitude twice that of the above current ?

A. I = 2I∫Sin(πt/2)
B. I = 2I∫Sin(2πt)
C. I = 2ISinπt
D. I = I∫sin(2πt)

A capacitor of capacitance 30µF is charged by a constant current of 10mA. If initially, the capacitor was uncharged what is the time taken for the potential difference across the capacitor to reach 300V ?

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A capacitor of capacitance 30µF is charged by a constant current of 10mA. If initially, the capacitor was uncharged what is the time taken for the potential difference across the capacitor to reach 300V ?

A. 0.9sec
B. 15 sec
C. 1.5x105sec
D. 0.9x102sec

The value of the steady current which when flowing through the same resistor produces heat at the same rate as the mean rate of heat produced by the alternating current is__________________?

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The value of the steady current which when flowing through the same resistor produces heat at the same rate as the mean rate of heat produced by the alternating current is__________________?

A. Average current
B. Sinusoidal current
C. r.m.s current
D. Net current