1.
The rms value of an AC source is 220 V. Its peak value is approximately
2.
An AC current is represented by i=5sin(100πt). Its frequency is
3.
The average power consumed in a purely inductive AC circuit is
4.
The average power consumed in a purely capacitive AC circuit is
5.
In a phasor diagram of a pure capacitive circuit, the current
6.
At resonance in a series LCR circuit,
7.
The condition for resonance is
8.
At resonance, the phase angle between current and voltage is
9.
A transformer can operate only with
10.
The efficiency of an ideal transformer is
11.
Assertion (A): A transformer cannot work with direct current. Reason (R): Mutual induction requires changing magnetic flux.
12.
Assertion (A): Power factor is unity at resonance. Reason (R): Voltage and current are in phase.
13.
The reactance of an inductor increases with
14.
The capacitive reactance decreases when
15.
If the frequency of AC is doubled, the inductive reactance becomes
16.
Match the Columns: Column–I P. Inductive Reactance Q. Capacitive Reactance R. Resonance S. Transformer Column–II 1. XL=ωLX_L=\omega LXL=ωL 2. Mutual induction 3. XC=1ωCX_C=\frac1{\omega C}XC=ωC1 4. Maximum current Choose the correct matching.
17.
A step-up transformer increases
18.
If the secondary coil has fewer turns than the primary coil, the transformer is
19.
In an ideal transformer, VpIp=
20.
Which quantity remains unchanged in an ideal transformer?
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