Free Capacitors MCQs with Answers
63 Capacitors MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Capacitors store electric charge and energy in an electric field between conductors. Work includes capacitance, the relation Q = CV, dielectric materials, charging and discharging, energy formulas, and combinations of capacitors in series and parallel. Electric potential difference is needed to understand why charge and stored energy change.
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63 questions · page 2 of 4
- A. ½ εᵣ.ε₀.E
- B. ½ ε₀.εᵣ.E2
- C. ε₀.εᵣ.E
- D. ε₀.εᵣ.E2
Explanation: Energy density is the total energy per unit volume of the capacitor, as the electrostatic energy stored in a parallel plate capacitor is…
Correct answer: ½ ε₀.εᵣ.E2- A. 79.5 μC
- B. 35.3 μC
- C. 79.5 pC
- D. 35.3 pC
Explanation: Q = 5.3 x 10^-5 CV = 6.0 VUsing the formula Q = CV, we get:C = Q/V = (5.3 x 10^-5 C)/(6.0 V) = 8.83 x 10^-6FNow, let's find the charge…
Correct answer: 79.5 μC- A. C = εₒA/d
- B. C = dA/εₒ
- C. C = d/Aεₒ
- D. C = dεₒ/A
Explanation: The capacitance of a parallel plate capacitor is directly proportional to the area of the plates (A) and the permittivity of free space…
Correct answer: C = εₒA/d- A. Capacitance remains same
- B. Capacitance becomes double
- C. Capacitance becomes four times
- D. Capacitance reduces to half
Explanation: The formula for capacitance is𝐶=ε𝐴 / 𝑑where,A is the area of the plate, d is the distance between the two parallel plates.If area is…
Correct answer: Capacitance becomes four times- A. increase linearly.
- B. decrease linearly.
- C. increase exponentially.
- D. decrease exponentially.
Explanation: During the charging of a capacitor in an electrical circuit, the charges on the capacitor plates increase exponentially until they reach a…
Correct answer: increase exponentially.- A. increase the capacitance.
- B. decrease the capacitance.
- C. make the capacitance zero.
- D. make the capacitance constant.
Explanation: A) increase the capacitance. Explanation: 1. When a dielectric material is inserted between the plates of a capacitor, the electric field…
Correct answer: increase the capacitance.- A. sum of their individual capacitances.
- B. product of their individual capacitances.
- C. sum of reciprocal of individual capacitances.
- D. product of reciprocal of individual capacitances.
Explanation: When two or more parallel plate capacitors are connected in parallel, their equivalent capacitance is the sum of their individual…
Correct answer: sum of their individual capacitances.- A. 2.5 C.
- B. 5.5 C.
- C. 12.5 C.
- D. 31.5 C.
Explanation: The relationship between charge (Q), capacitance (C), and potential difference (V) across a capacitor is given by the formula:Q = C ×…
Correct answer: 31.5 C.- A. Charge.
- B. Voltage.
- C. Current.
- D. Capacitance.
Explanation: When capacitors are connected in series, the same charge flows through each capacitor, meaning the charge remains constant across all the…
Correct answer: Charge.- A. Metals
- B. Dielectrics
- C. Conductors
- D. Semi-conductors
Explanation: The correct answer is Metals because they have free charges that can move easily. Dielectrics do not have free charges and are insulators.
Correct answer: Metals- A. Time constant.
- B. Electric power.
- C. Electric current.
- D. Applied voltage.
Explanation: The correct answer is Time constant. This concept is fundamental to understanding how quickly a capacitor can charge or discharge in a…
Correct answer: Time constant.- A. Is zero.
- B. Is minimum.
- C. Is maximum.
- D. Cannot be determined.
Explanation: In an electric circuit, when a capacitor is fully charged, it acts as an open circuit.
Correct answer: Is zero.- A. C1 + C3
- B. 1/C1 + 1/C2
- C. C1 + C2 + C3
- D. 1/C1 + 1/C2 + 1/C3
Explanation: The correct answer is1/C1 + 1/C2 + 1/C3This formula is used to calculate the equivalent capacitance for capacitors in series.
Correct answer: 1/C1 + 1/C2 + 1/C3- A. The potential difference across the capacitor increases and the stored energy remains the same.
- B. The potential difference across the capacitor decreases and the stored energy decreases.
- C. The potential difference across the capacitor remains the same and the stored energy remains the same.
- D. The potential difference across the capacitor decreases and the stored energy increases.
Explanation: When a dielectric slab is inserted into a charged capacitor that is isolated (battery detached), the potential difference across the…
Correct answer: The potential difference across the capacitor decreases and the stored energy increases.- A. 0 µF.
- B. 1 µF.
- C. 5 µF.
- D. 20 µF.
Explanation: When two capacitors, each with a capacitance of 10 µF, are connected in series, the formula for their equivalent capacitance is 1/C_eq =…
Correct answer: 5 µF.- A. Increases.
- B. Decreases.
- C. Becomes zero.
- D. Remains the same.
Explanation: The correct answer is that the capacitance of a parallel plate capacitor increases due to the electric polarisation of the dielectric.
Correct answer: Increases.- A. 0.83 μF
- B. 1.83 μF
- C. 3 μF
- D. 6 μF
Explanation: To find the equivalent capacitance, determine whether the capacitors are in series or parallel.
Correct answer: 6 μF- A. C1 + C2 + C3
- B. C2 / (C1 + C3)
- C. C1 / (C2 + C3)
- D. 1/C1 + 1/C2 + 1/C3
Explanation: The correct answer is Option A:C1 + C2 + C3. When capacitors are connected in parallel, the total capacitance is the sum of the individual…
Correct answer: C1 + C2 + C3- A. Increase.
- B. Decrease.
- C. Become zero.
- D. Remain the same.
Explanation: When capacitors are connected in series, the reciprocal of the equivalent capacitance is the sum of the reciprocals of the individual…
Correct answer: Decrease.- A. 0.5C
- B. 0.25C
- C. 4C
- D. C
Explanation: C= AEo/d d'=1/2d A=1/2A C=1/2AEo/1/2d C=1/2AEo/1/2d C-AEo/d Unchanged
Correct answer: C