1. Can the capacitor fully charge using alternating current?
A. yes
B. no
C. may or may not
D. depend on the value of capacitance
Answer: A
No, the capacitor cannot be fully charged using alternating current because as soon as the capacitor charges, the alternating current reverses its polarity thereby discharging it.
2. What is the resistance offered by a capacitor?
A. Susceptance
B. Conductance
C. Admittance
D. Reactance
Answer: D
The resistance offered to alternating current by an inductor or capacitor is known as reactance which is equivalent to the resistance of the resistor.
3. The combination of resistance and reactance known as ___________
A. Susceptance
B. Impedance
C. Conductance
D. Admittance
Answer: B
The combination of resistance and reactance is known as impedance. It is the equivalent resistance of an RLC alternating circuit.
4. What is the relation between reactance, resistance, and impedance?
A. Z = R+jX
B. Z = R+X
C. Z = R-X
D. Z = R-jX
Answer: A
The combination of resistance and reactance is known as impedance.
Z = R+jX
Where
Z is impedance
R is resistance and X is reactance.
5. What is the real part of the impedance of the RLC circuit?
A. Resistance
B. Conductance
C. Admittance
D. Reactance
Answer: A
The combination of resistance and reactance is known as impedance.
Z = R+jX
where
Z is impedance
R is resistance
X is reactance.
R is a real part of Z.
6. What is the imaginary part of the impedance of the RLC circuit?
A. Resistance
B. Conductance
C. Admittance
D. Reactance
Answer: D
The combination of resistance and reactance is known as impedance.
Z = R+jX
where
Z is impedance
R is resistance
X is reactance.
X is the imaginary part of Z.
7. Which type of current can be stored in a capacitor?
A. Alternating current
B. Direct current
C. Both alternating current and direct current
D. Neither alternating current nor direct current
Answer: B
Only direct current can be stored in the capacitor. The capacitor cannot be fully charged using alternating current because as soon as the capacitor charges, the alternating current reverses its polarity thereby discharging it. So, we cannot store ac current in the capacitor.
8. If in an alternating current circuit, resistance is 5 ohm, capacitive reactance is 12 ohm, what is the impedance?
A. 5 ohm
B. 10 ohm
C. 12 ohm
D. 13 ohm
Answer: D
R = 5Ω, XC = 12Ω
Z2 = R2+XC2
Substituting the values we get,
Z2 = 52 + 122
Z2 = 169
Z = 13 Ω.
9. If in an alternating current circuit, impedance is 26 ohm, capacitive reactance is 24 ohm, what is the resistance?
A. 25 ohm
B. 10 ohm
C. 12 ohm
D. 23 ohm
Answer: B
Z = 26Ω, XC = 24Ω
Z2 = R2+XC2
Substituting the values we get,
262 = R2 + 242
676 = R2 + 576
R2 = 100
R = 10 Ω.
10. If in an alternating current circuit, a capacitance of 30 µF is connected to a supply of 200V,50Hz. Find the current in the circuit.
