Power in AC Circuits, Wattless Current NEET Questions

Physics - Electromagnetic Induction and Alternating Currents

Power in AC Circuits, Wattless Current MCQ Questions


13.
The average value of sin(ωt)·cos(ωt) over a complete cycle is:
A.
1/2
B.
1/√2
C.
Zero
D.
1
😑 View Answer Rough Work Error
ANSWER :
C. Zero
14.
Power dissipated in a series LCR circuit can also be written as:
A.
I_rms × Z
B.
V_rms × Z
C.
I_rms² × Z
D.
I_rms² × R
😑 View Answer Rough Work Error
ANSWER :
D. I_rms² × R
15.
Average power in an AC circuit is also equal to:
A.
V_R × I (where V_R is voltage across resistor)
B.
V × I (with V = total source voltage)
C.
V × I × tan(φ)
D.
I × Z × cos(φ)
😑 View Answer Rough Work Error
ANSWER :
A. V_R × I (where V_R is voltage across resistor)
16.
If V = 200 V (RMS) is applied to a series RL circuit with R = 30 Ω, X_L = 40 Ω, the average power is:
A.
240 W
B.
1600 W
C.
800 W
D.
480 W
😑 View Answer Rough Work Error
ANSWER :
D. 480 W
17.
In an AC circuit, the instantaneous power is given by p(t) = V₀ I₀ sin(ωt) sin(ωt - φ). The maximum instantaneous power is:
A.
V₀ I₀ × cos(φ)
B.
V₀ I₀ × sin(φ)
C.
V₀ I₀
D.
V₀ I₀/2
😑 View Answer Rough Work Error
ANSWER :
C. V₀ I₀
18.
An AC source with V_rms = 100 V is connected across a 25 Ω resistor. The energy dissipated in 1 minute is:
A.
1200 J
B.
12000 J
C.
24000 J
D.
6000 J
😑 View Answer Rough Work Error
ANSWER :
C. 24000 J