Electromagnetism - SS2 Physics Past Questions and Answers - page 3
When two capacitors are connected in parallel, the total capacitance is:
The sum of the individual capacitances.
The reciprocal of the sum of the reciprocals of the individual capacitances.
The average of the individual capacitances.
The product of the individual capacitances.
The dielectric constant of a material is a measure of:
Its resistance to electric current.
Its ability to store charge.
Its ability to conduct electricity.
Its ability to withstand voltage.
The unit of capacitance is:
Farad (F).
Ohm (Ω).
Volt (V).
Ampere (A).
A capacitor has a capacitance of 5 μF and is charged to a voltage of 10 V. What is the charge stored on the capacitor?
Given: C = 5 μF = 5 × 10(-6) F, V = 10 V
Q = C × V
Q = (5 × 10(-6) F) × (10 V)
Q = 50 × 10(-6) C
Q = 50 μC
Therefore, the charge stored on the capacitor is 50 μC.
Users' Answers & CommentsA parallel plate capacitor with a capacitance of 8 pF is connected to a 12 V battery. What is the energy stored in the capacitor?
Given: C = 8 pF = 8 × 10(-12) F, V = 12 V
The energy stored in the capacitor is given by the formula: E = 1/2CV2
E = 1/2 × (8 × 10(-12) F) × (12 V)2
E = 1/2 × 8 × 10(-12) F × 144 V2
E = 576 × 10(-12) F × V2
E = 576 × 10(-12) J
Therefore, the energy stored in the capacitor is 576 × 10(-12) J.
Users' Answers & CommentsTwo capacitors, C1 and C2, are connected in parallel. C1 has a capacitance of 6 μF, and C2 has a capacitance of 8 μF. What is the total capacitance of the combination?
The total capacitance of capacitors connected in parallel is given by the sum of the individual capacitances.
Total capacitance = C1 + C2
Total capacitance = 6 μF + 8 μF
Total capacitance = 14 μF
Therefore, the total capacitance of the combination is 14 μF.
Users' Answers & CommentsThree capacitors, C1, C2, and C3, are connected in series. C1 has a capacitance of 4 μF, C2 has a capacitance of 6 μF, and C3 has a capacitance of 8 μF. What is the total capacitance of the combination?
The total capacitance of capacitors connected in series is given by the reciprocal of the sum of the reciprocals of the individual capacitances.
1/Total capacitance = 1/C1 + 1/C2 + 1/C3
1/Total capacitance = 1/4 μF + 1/6 μF + 1/8 μF
1/Total capacitance = (3/12 + 2/12 + 3/24) μF
1/Total capacitance = 8/24 μF
1/Total capacitance = 1/3 μF
Total capacitance = 3 μF
Therefore, the total capacitance of the combination is 3 μF.
Users' Answers & CommentsIn an RC circuit, the time constant is defined as:
The time taken for the capacitor to fully charge
The time taken for the capacitor to fully discharge
The product of resistance and capacitance
The time taken for the voltage across the capacitor to reach 63.2% of its maximum value
In an RC circuit, if the resistance is increased while the capacitance remains constant, what happens to the time constant?
Increases
Decreases
Remains the same
Cannot be determined without additional information
A 10 kΩ resistor and a 100 μF capacitor are connected in series in an RC circuit. What is the time constant of the circuit?
1 ms
10 ms
100 ms
1 s
Explanation: The time constant (τ) of an RC circuit is given by the product of resistance (R) and capacitance (C). τ = RC = (10,000 Ω) × (100 × 10(-6) F) = 1 × 10(-3) s = 10 ms.
Users' Answers & Comments