Free Electrostatics MCQs with Answers
831 Electrostatics MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Electrostatics describes forces between charges through Coulomb's law, electric fields and field intensity, then uses electric potential to measure energy per unit charge. Capacitors store charge and electrical energy, with capacitance depending on geometry and dielectric material, not simply on the amount of charge present.
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Read the Electrostatics notesFree MDCAT chapter notes with key terms831 questions · page 4 of 42
- 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. F/4
- B. F/2
- C. 2F
- D. 4F
Explanation: The force between two charges in a medium is given by Coulomb's law, which states that the force is inversely proportional to the…
Correct answer: F/4- A. 1.48 N (attractive)
- B. 1.48 N (repulsive)
- C. 2.96 (repulsive)
- D. Zero
Explanation: The charges after adding -5C become:Q1 = +5-5 = 0CQ2 = -12-5 = -17CUsing formulaF= kq1q2/r21.48 = 9(109) (0)(17)/r2Since one charge is 0C…
Correct answer: Zero- A. Gases
- B. Metals
- C. Liquids
- D. Insulators
Explanation: Insulators (D): Insulators, particularly those specifically designed as dielectric materials, have high dielectric constants.
Correct answer: Insulators- A. two-third of the previous value.
- B. one-third of the previous value.
- C. one-fourth of the previous value.
- D. three-fourth of the previous value.
Explanation: When the distance between two identical charges is doubled, the force of repulsion between them decreases by a factor of 1/2^2 = 1/4.
Correct answer: one-fourth of the previous value.- A. Increase
- B. Decrease
- C. Remain constant
- D. Vary unpredictably
Explanation: When a dielectric slab is inserted between two point charges, it polarizes in response to the electric field created by the charges.
Correct answer: Decrease- A. 9 x 10^5 N / C
- B. 3 x 10^3 N / C
- C. 4.5 x 10^5 N / C
- D. 9 x 10^-5 N / C
Explanation: The electric field E due to a point charge q at a distance r from the charge is given by Coulomb's law: E=kq /r2where:k is Coulomb's…
Correct answer: 9 x 10^5 N / C- A. 3 x 10^5N/C
- B. 4.5 x 10^5N/C
- C. 9 x 10^5N/C
- D. 3 x 10^3N/C
Explanation: The electric field E due to a point charge q at a distance r from the charge is given by Coulomb's law: E=kq /r2where:k is Coulomb's…
Correct answer: 9 x 10^5N/C- A. 4E
- B. E/2
- C. E/4
- D. 2E
Explanation: Between two parallel plates, the electric field strength is given by:E = V/dIf the distance is halved, electric field strength is doubled…
Correct answer: 2E- A. 1.82 x 10^-15 N
- B. 3.00 x 10^-16 N
- C. 1.92 x 10^-15 N
- D. 3.00 x 10^-15 N
- E. 5.00 x 10^-15 N
Explanation: To solve this problem, we first calculate the electric field (E) between the parallel plates using the formula E = V/d, where V is the…
Correct answer: 1.92 x 10^-15 N- A. Newton meter
- B. Newton / meter
- C. Newton coulomb
- D. Newton / coulomb
Explanation: The formula for the electric field strength can be written as:E=Force/ChargeSubstituting the corresponding SI units for these two…
Correct answer: Newton / coulomb- A. Electric field intensity
- B. Electric flux
- C. Magnetic intensity
- D. Magnetic flux
Explanation: W = FdF = qEW = qEdW/q = V = EdV/d = EThe potential gradient is represented by -Δd/Δr.
Correct answer: Electric field intensity- A. 4 cm/s2
- B. 2 cm/s^2
- C. 40 cm/s2
- D. 20 cm/s2
Explanation: 2x10-6 x 20 / 2x10-3 = 0.02 m/s2 x100 = 2cm/s2
Correct answer: 2 cm/s^2- A. E
- B. 2E
- C. 4E
- D. 8E
Explanation: Electric field is calculated by the formula = Voltage / Distance so doubling the separation of plates decreases the electric field by 2…
Correct answer: 2E