Power in AC Circuits, Wattless Current NEET Questions

Physics - Electromagnetic Induction and Alternating Currents

Power in AC Circuits, Wattless Current MCQ Questions


1.
The instantaneous power dissipated in an AC circuit is:
A.
p(t) = V_rms × I_rms
B.
p(t) = v(t)·i(t)
C.
p(t) = V₀ × I₀
D.
p(t) = V·I (constant)
😑 View Answer Rough Work Error
ANSWER :
B. p(t) = v(t)·i(t)
2.
The average power delivered by an AC source to a circuit is given by:
A.
P_avg = V_rms × I_rms
B.
P_avg = V₀ × I₀
C.
P_avg = V_rms × I_rms × cos(φ)
D.
P_avg = V₀ × I₀/2
😑 View Answer Rough Work Error
ANSWER :
C. P_avg = V_rms × I_rms × cos(φ)
3.
If v(t) = V₀ sin(ωt) and i(t) = I₀ sin(ωt - φ), the average power over one cycle is:
A.
(V₀ I₀ sin φ)/2
B.
V₀ I₀
C.
(V₀ I₀ cos φ)/2
D.
(V₀ I₀)/2
😑 View Answer Rough Work Error
ANSWER :
C. (V₀ I₀ cos φ)/2
4.
In an AC circuit, the average power dissipated in a pure resistor (R only) is:
A.
Maximum value V₀·I₀
B.
V_rms × I_rms
C.
Zero
D.
V_rms × I_rms × 0.5
😑 View Answer Rough Work Error
ANSWER :
B. V_rms × I_rms
5.
In an AC circuit with a pure resistor of resistance R, V_rms = 220 V. Average power dissipated is:
A.
2V_rms²/R
B.
V_rms² × R
C.
V_rms²/R
D.
V_rms²/(2R)
😑 View Answer Rough Work Error
ANSWER :
C. V_rms²/R
6.
Average power dissipated in a pure inductor in AC circuit is:
A.
V_rms²/(2X_L)
B.
(V_rms × I_rms)/2
C.
V_rms × I_rms
D.
Zero
😑 View Answer Rough Work Error
ANSWER :
D. Zero