Q. 65.0( 3 Votes )
(i) Given that E = E0Sin(ωt)
I = I0Sin(ωt + π/4)
It can be seen from the above two equations that phase angle of current at any point is greater than that of voltage by an amount of π/4. This means current leads the voltage in the circuit. This happens in a capacitive circuit. Therefore the element in the black box is a capacitor.
Vc = VR
Xc = R
Impedance Z =
Z = R√2
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