Question 25

A device X is connected across an ac source of voltage V=V_{o} sin ωt. The current through X is given as I=I_{o} sin (ωt+π/2).

(a) Identify the device X and write the expression for its reactance.

(b) Draw graphs showing variation of voltage and current with time over one cycle of ac, for X.

(c) How does the reactance of the device X vary with the frequency of the ac? Show this variation graphically.

(d) Draw the phasor diagram for the device X.

Answer

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