The line the draws power supply to your house from street has

Options

A. zero average current
B. 220 V average voltage
C. voltage and current out of phasea by `90^(@)`
D. voltage and current possibly differing in phase `phi` such that `|phi| lt (pi)/(2)`

Answer

A, D

Explanation

The line that draws power supply to our house from street supplies alternating current, whose average `value//mean` value over a cycle is zero. As the line has some resistance `(R != 0)`, thereofore, voltage and current differ in phase `phi` such that `|phi| lt pi //2`. choice (a) and (d) are correct.