Capacitance
Q. A capacitor has a capacitance of 4μF and is charged to 12V. What is the charge on the capacitor?
A.
48μC
B.
12μC
C.
4μC
D.
3μC
Show solution
Solution
Charge (Q) on a capacitor is given by Q = C * V. Thus, Q = 4μF * 12V = 48μC.
Correct Answer: A — 48μC
Learn More →
Q. A capacitor is charged to a voltage of 10V and then connected to a resistor. What will happen to the voltage across the capacitor over time?
A.
It increases
B.
It decreases exponentially
C.
It remains constant
D.
It oscillates
Show solution
Solution
The voltage across the capacitor decreases exponentially over time when connected to a resistor due to discharge.
Correct Answer: B — It decreases exponentially
Learn More →
Q. A capacitor is charged to a voltage V and then connected to a resistor R. What is the time constant of the circuit?
A.
RC
B.
C/R
C.
R/C
D.
1/RC
Show solution
Solution
The time constant (τ) of an RC circuit is given by τ = RC.
Correct Answer: A — RC
Learn More →
Q. A capacitor is charged to a voltage V and then disconnected from the battery. If the distance between the plates is increased, what happens to the charge?
A.
Increases
B.
Decreases
C.
Remains the same
D.
Becomes zero
Show solution
Solution
When a capacitor is disconnected from the battery, the charge remains constant. Increasing the distance decreases capacitance but does not affect the charge.
Correct Answer: C — Remains the same
Learn More →
Q. A capacitor is charged to a voltage V and then disconnected from the battery. If the distance between the plates is doubled, what happens to the voltage across the capacitor?
A.
It doubles
B.
It halves
C.
It remains the same
D.
It quadruples
Show solution
Solution
When the distance is doubled, the capacitance decreases, leading to an increase in voltage since Q = CV is constant.
Correct Answer: A — It doubles
Learn More →
Q. A capacitor is charged to a voltage V and then disconnected from the battery. What happens to the charge on the capacitor?
A.
It increases
B.
It decreases
C.
It remains constant
D.
It becomes zero
Show solution
Solution
Once disconnected from the battery, the charge on the capacitor remains constant as there is no path for charge to flow.
Correct Answer: C — It remains constant
Learn More →
Q. A capacitor is charged to a voltage V and then disconnected from the battery. What happens to the charge on the capacitor if the distance between the plates is increased?
A.
Charge increases
B.
Charge decreases
C.
Charge remains the same
D.
Charge becomes zero
Show solution
Solution
When a capacitor is disconnected from the battery, the charge remains constant. Increasing the distance decreases capacitance but does not change the charge.
Correct Answer: C — Charge remains the same
Learn More →
Q. A capacitor is charged to a voltage V and then disconnected from the battery. What happens to the charge on the capacitor if the voltage is doubled?
A.
Charge doubles
B.
Charge halves
C.
Charge remains the same
D.
Charge quadruples
Show solution
Solution
The charge on a capacitor is given by Q = C * V. If the voltage is doubled, the charge also doubles, assuming capacitance remains constant.
Correct Answer: A — Charge doubles
Learn More →
Q. A capacitor is charged to a voltage V and then the voltage is halved. What happens to the energy stored in the capacitor?
A.
It doubles
B.
It halves
C.
It remains the same
D.
It becomes zero
Show solution
Solution
The energy stored in a capacitor is proportional to the square of the voltage (U = 1/2 CV²). If the voltage is halved, the energy becomes U/4.
Correct Answer: B — It halves
Learn More →
Q. A capacitor of capacitance C is charged to a voltage V and then connected in parallel with another uncharged capacitor of capacitance C. What is the final voltage across the capacitors?
Show solution
Solution
When connected in parallel, the total charge is conserved. The final voltage across both capacitors is V/2.
Correct Answer: A — V/2
Learn More →
Q. A capacitor of capacitance C is charged to a voltage V. If the voltage is halved, what is the new energy stored in the capacitor?
Show solution
Solution
The energy stored in a capacitor is given by U = 1/2 CV². If the voltage is halved, the new energy becomes U' = 1/2 C(V/2)² = U/4.
Correct Answer: A — U/4
Learn More →
Q. A capacitor of capacitance C is connected to a battery of voltage V. If the battery is removed and the capacitor is connected to another capacitor of capacitance 2C, what is the final voltage across the combination?
Show solution
Solution
When the charged capacitor C is connected to an uncharged capacitor 2C, the final voltage is V_final = Q_total / C_eq = V/(1 + 1/2) = V/3.
Correct Answer: B — V/2
Learn More →
Q. If a capacitor has a capacitance of 10 µF and is charged to 5 V, what is the charge on the capacitor?
A.
50 µC
B.
5 µC
C.
2 µC
D.
10 µC
Show solution
Solution
The charge (Q) on a capacitor is given by Q = C * V. Here, Q = 10 µF * 5 V = 50 µC.
Correct Answer: A — 50 µC
Learn More →
Q. If a capacitor is charged and then short-circuited, what happens to the charge on the capacitor?
A.
It remains the same
B.
It is discharged
C.
It increases
D.
It becomes zero
Show solution
Solution
When a charged capacitor is short-circuited, the charge flows through the circuit, and the charge on the capacitor becomes zero.
Correct Answer: B — It is discharged
Learn More →
Q. If a capacitor is charged to a voltage V and then connected in parallel with an uncharged capacitor, what will be the final voltage across both capacitors?
Show solution
Solution
When connected in parallel, charge redistributes, and the final voltage across both capacitors will be V/2.
Correct Answer: B — V/2
Learn More →
Q. If a capacitor is charged to a voltage V and then connected to a resistor R, what is the time constant of the circuit?
A.
RC
B.
R/C
C.
C/R
D.
1/RC
Show solution
Solution
The time constant τ of an RC circuit is given by τ = R * C.
Correct Answer: A — RC
Learn More →
Q. If a capacitor is charged to a voltage V and then short-circuited, what happens to the charge on the capacitor?
A.
It remains the same
B.
It becomes zero
C.
It doubles
D.
It halves
Show solution
Solution
Short-circuiting a capacitor allows charge to flow off, resulting in the charge becoming zero.
Correct Answer: B — It becomes zero
Learn More →
Q. If a capacitor is charged to a voltage V and then short-circuited, what happens to the energy stored in the capacitor?
A.
It is conserved
B.
It is dissipated as heat
C.
It increases
D.
It becomes zero
Show solution
Solution
When a capacitor is short-circuited, the stored energy is dissipated as heat in the circuit.
Correct Answer: B — It is dissipated as heat
Learn More →
Q. If a capacitor is connected to a DC voltage source, what will happen to the current over time?
A.
It remains constant
B.
It increases
C.
It decreases to zero
D.
It oscillates
Show solution
Solution
In a DC circuit, the current through a capacitor decreases to zero as it becomes fully charged.
Correct Answer: C — It decreases to zero
Learn More →
Q. If a capacitor is connected to an AC source, how does the current behave?
A.
It is constant
B.
It leads the voltage
C.
It lags the voltage
D.
It is zero
Show solution
Solution
In an AC circuit, the current through a capacitor leads the voltage by 90 degrees.
Correct Answer: B — It leads the voltage
Learn More →
Q. If a capacitor is fully discharged and then connected to a voltage source, what is the initial current through the circuit?
A.
Zero
B.
Maximum
C.
Depends on resistance
D.
Infinite
Show solution
Solution
When a capacitor is fully discharged and connected to a voltage source, the initial current is maximum as it starts charging.
Correct Answer: B — Maximum
Learn More →
Q. If a capacitor of capacitance 4μF is connected to a 12V battery, what is the charge on the capacitor?
A.
48μC
B.
12μC
C.
4μC
D.
24μC
Show solution
Solution
Charge (Q) on a capacitor is given by Q = C * V. Here, Q = 4μF * 12V = 48μC.
Correct Answer: A — 48μC
Learn More →
Q. If a capacitor of capacitance C is charged to a voltage V, what is the energy stored in the capacitor?
A.
1/2 CV^2
B.
CV
C.
V^2 / C
D.
C / V
Show solution
Solution
The energy (U) stored in a capacitor is given by the formula U = 1/2 CV^2.
Correct Answer: A — 1/2 CV^2
Learn More →
Q. If a capacitor of capacitance C is connected to a voltage source V, what is the charge on the capacitor?
A.
C/V
B.
V/C
C.
CV
D.
V^2/C
Show solution
Solution
The charge (Q) on a capacitor is given by Q = CV when connected to a voltage source V.
Correct Answer: C — CV
Learn More →
Q. If a capacitor with capacitance C is connected to a voltage V, what is the charge stored in the capacitor?
A.
C/V
B.
V/C
C.
C * V
D.
C + V
Show solution
Solution
The charge (Q) stored in a capacitor is given by the formula Q = C * V.
Correct Answer: C — C * V
Learn More →
Q. If the distance between the plates of a capacitor is doubled, what happens to its capacitance?
A.
It doubles
B.
It halves
C.
It remains the same
D.
It quadruples
Show solution
Solution
Capacitance is inversely proportional to the distance between the plates. If the distance d is doubled, the capacitance C becomes C/2.
Correct Answer: B — It halves
Learn More →
Q. If the distance between the plates of a capacitor is halved, what happens to its capacitance?
A.
It doubles
B.
It halves
C.
It remains the same
D.
It quadruples
Show solution
Solution
Capacitance is inversely proportional to the distance between the plates. If the distance is halved, the capacitance doubles.
Correct Answer: A — It doubles
Learn More →
Q. If two capacitors of capacitance C1 and C2 are connected in series, what is the equivalent capacitance?
A.
C1 + C2
B.
1 / (1/C1 + 1/C2)
C.
C1 * C2 / (C1 + C2)
D.
C1 - C2
Show solution
Solution
The equivalent capacitance C_eq of capacitors in series is given by 1 / C_eq = 1 / C1 + 1 / C2.
Correct Answer: B — 1 / (1/C1 + 1/C2)
Learn More →
Q. In a capacitor, if the plate area is increased while keeping the separation constant, what happens to the capacitance?
A.
It increases
B.
It decreases
C.
It remains the same
D.
It becomes zero
Show solution
Solution
Capacitance is directly proportional to the plate area A. Increasing A increases capacitance.
Correct Answer: A — It increases
Learn More →
Q. In a capacitor, what does the dielectric constant represent?
A.
The ability to store charge
B.
The ability to resist electric field
C.
The ability to increase capacitance
D.
The ability to conduct electricity
Show solution
Solution
The dielectric constant represents the ability of a material to increase the capacitance of a capacitor compared to a vacuum.
Correct Answer: C — The ability to increase capacitance
Learn More →
Showing 1 to 30 of 53 (2 Pages)