Electric field strength is:
- Work done
- Energy
- Force per unit charge
- Charge per force
Show answer and explanation
Answer: C. Force per unit charge
Electric field strength (intensity) is defined as force per unit positive test charge, E = F/q.
FSC Physics: Electrostatics, questions with answers
Practise 34 real Federal Board questions on Electrostatics from 2023 to 2026. See the answer and explanation as soon as you answer.
34real questions
14multiple choice
5exam sessions
About Electrostatics in FSC Physics
Electrostatics is one of the 14 main chapters in our Federal Board FSC Physics question bank (11th and 12th class), and about 7% of its real questions come from it. Tayyari Karo has 34 real questions on this chapter from 2023 to 2026; 14 are multiple choice and marked instantly, and the rest are short and long questions with a model answer. By difficulty: 26 medium, 8 easy.
Work through the questions below, then open the explanation for each one. Redo the ones you missed a few days later.
Try 8 real questions
These are real past-paper questions. Think of your answer first, then open the explanation.
Which of the following CANNOT be accelerated using electric field?
- Proton
- Ion
- Electron
- Neutron
Show answer and explanation
Answer: D. Neutron
A neutron carries no electric charge, so an electric field exerts no force on it and cannot accelerate it.
Coulomb force between two electric charges is 120 N. If the distance between the charges is doubled, the coulomb force will be:
- 15 N
- 30 N
- 60 N
- 40 N
Show answer and explanation
Answer: B. 30 N
F ∝ 1/r². Doubling r reduces F to 1/4 of its original value: 120/4 = 30 N.
The electric dipole moment is the product of:
- Charge and force
- Charge and electric field
- Charge and voltage
- Charge and displacement
Show answer and explanation
Answer: D. Charge and displacement
Dipole moment p = q×d, the product of one charge and the separation (displacement) between the two charges.
According to Gauss's law, the electric field inside a hollow conductor is:
- Decreasing
- Zero
- Constant
- Increasing
Show answer and explanation
Answer: B. Zero
There is no enclosed charge inside a hollow conductor, so by Gauss's law the electric field inside is zero.
There are two charges 1 μC and 6 μC. The ratio of forces acting on them will be:
- 1:25
- 1:6
- 1:1
- 6:1
Show answer and explanation
Answer: C. 1:1
By Newton's third law, the force each charge exerts on the other in a mutual electrostatic interaction is equal in magnitude and opposite in direction — ratio 1:1.
Deduce the dimensions of k from Coulomb's law F = kq₁q₂/r².
Show model answer
k = Fr²/(q₁q₂)
[F] = MLT⁻², [r²] = L², [q₁q₂] = A²T² (charge = current × time)
[k] = (MLT⁻²)(L²)/(A²T²)
[k] = ML³T⁻⁴A⁻²
An object having a net charge of 24 μC is placed in a uniform electric field of 610 N/C directed vertically. What is the mass of this object if it floats in the field?
Show model answer
For the object to float, the electric force balances gravity: qE = mg
m = qE/g = (24×10⁻⁶)(610)/9.8 = 0.01464/9.8
m ≈ 1.49 × 10⁻³ kg (1.49 g)
Sessions with Electrostatics questions
| Session | Questions |
|---|---|
| 2026 Annual | 4 |
| 2025 1st Annual | 10 |
| 2025 2nd Annual | 11 |
| 2024 Annual | 5 |
| 2023 Annual | 4 |
Common questions
What does the Electrostatics chapter cover on this page?
34 real Federal Board (FBISE) Physics questions on Electrostatics from 2023 to 2026, for 11th and 12th class. Each one shows the session it came from.
Are the answers official?
No. We could not find an official FBISE marking scheme for these papers, so the answers and explanations are written by Tayyari Karo for practice. Check anything important with your teacher or textbook.
Is it free?
You can start free with no signup. A small set of papers per subject is free, and Premium unlocks the full question bank.