⚡ Chapter 15: Electrostatics – Exercise Short Questions
Prepared by Muhammad Tayyab, Subject Specialist Physics, Govt Christian High School Daska. Based on PECTAA 2026 syllabus (National Curriculum 2023).
📖 What's Inside: This chapter covers Coulomb's law, electric field, conductors, insulators, applications of electrostatics, electrical breakdown, and dangers of static electricity. Each exercise short question is presented with the exact exam-ready answer as per the official PECTAA 2026 Physics curriculum. Perfect for Punjab Boards (Lahore, Gujranwala, Multan, etc.) and all BISE boards across Pakistan.
📚 Related Resources – Chapter 15: Electrostatics
Electrostatics covers Coulomb's law, electric field, potential, capacitance, charging by induction, electroscope, lightning, corona discharge, and applications. Includes solved examples and numerical problems.
📖 Exercise Short Questions & Answers (PECTAA 2026)
15.1 State Coulomb's law of electrostatics and write its mathematical form.
Coulomb's law states that; The magnitude of the electrostatic force between two point charges is directly proportional to the product of magnitude of these charges and inversely proportional to the square of the distance between them. Mathematically, it is given by
\[F = k\frac{q_1q_2}{r^2}\]
If the medium between the two charges is air, then the value of \(k\) in SI units will be \(9 \times 10^9 Nm^2 C^{-2}\).
Coulomb's law states that; The magnitude of the electrostatic force between two point charges is directly proportional to the product of magnitude of these charges and inversely proportional to the square of the distance between them. Mathematically, it is given by
\[F = k\frac{q_1q_2}{r^2}\]
If the medium between the two charges is air, then the value of \(k\) in SI units will be \(9 \times 10^9 Nm^2 C^{-2}\).
15.2 What is an electric field?
An electric field is the region around a charge where it exerts a force on other charges. Mathematically
\[E = k\frac{q}{r^2}\]
An electric field is the region around a charge where it exerts a force on other charges. Mathematically
\[E = k\frac{q}{r^2}\]
15.3 Give two examples each of electrical conductors and electrical insulators.
Examples of electrical conductors are copper, aluminium, silver, graphite, and electrolytes, while examples of electrical insulators are rubber, plastic, glass, wood, and ceramics.
Examples of electrical conductors are copper, aluminium, silver, graphite, and electrolytes, while examples of electrical insulators are rubber, plastic, glass, wood, and ceramics.
15.4 List some applications of electrostatics in daily life.
Applications of electrostatics include:
i. Photocopier: Photocopier uses electrostatic charges to copy documents.
ii. Electrostatic Precipitator: Electrostatic precipitator removes particulate matter from industrial exhaust gases.
iii. Electroscope: Electroscope detects electric charges.
iv. Lightning conductors: Lightning conductors protect buildings from lightning strikes.
Applications of electrostatics include:
i. Photocopier: Photocopier uses electrostatic charges to copy documents.
ii. Electrostatic Precipitator: Electrostatic precipitator removes particulate matter from industrial exhaust gases.
iii. Electroscope: Electroscope detects electric charges.
iv. Lightning conductors: Lightning conductors protect buildings from lightning strikes.
15.5 What happens when like charges and unlike charges are brought close to each other?
Like charges repel each other, whereas unlike charges attract each other.
Like charges repel each other, whereas unlike charges attract each other.
15.6 What is meant by electrical breakdown, and when does it occur?
Electrical breakdown is the process in which a strong electric field ionizes a gas (or insulating material), making it conductive. It occurs when the electric field becomes strong enough to overcome the insulating property of the medium.
Electrical breakdown is the process in which a strong electric field ionizes a gas (or insulating material), making it conductive. It occurs when the electric field becomes strong enough to overcome the insulating property of the medium.
15.7 What are the dangers of static electricity?
The dangers of static electricity include:
i. Minor shocks when touching metal objects.
ii. Clothes clinging together.
iii. In industrial settings, it can damage electronic components.
iv. It can ignite flammable substances.
v. It can disrupt manufacturing processes.
The dangers of static electricity include:
i. Minor shocks when touching metal objects.
ii. Clothes clinging together.
iii. In industrial settings, it can damage electronic components.
iv. It can ignite flammable substances.
v. It can disrupt manufacturing processes.
📐 Key Formulas – Electrostatics
Coulomb's Law: \( F = k \frac{q_1 q_2}{r^2} \)
Electric Field Intensity: \( E = \frac{F}{q_0} \)
Electric Field (Point Charge): \( E = k \frac{q}{r^2} \)
Electric Potential: \( V = \frac{W}{q} \)
Coulomb's Constant: \( k = 9 \times 10^9 \, \text{Nm}^2\text{C}^{-2} \)
Quantization of Charge: \( q = ne \)
Unit 10Thermal Physics
Unit 11Transfer of Thermal Energy
Unit 12Waves
Unit 13Sound
Unit 14Light
Unit 15✨ Electrostatics
Unit 16Electricity
Unit 17Electromagnetism
Unit 18Electromagnetic Induction & EM Waves
Unit 19Electronics
Unit 20Atomic and Nuclear Physics
Unit 21Space and Environment
📖 Complete syllabus coverage for Class 10 Physics (PECTAA 2026) – Units 10 to 21
💡 Exam Tip:
For board exams, define key terms precisely, mention formulas with units, and relate to real-life examples. These exercise questions follow the PECTAA 2026 pattern and are prepared by Subject Specialist Muhammad Tayyab.
Created by Hira Science Academy | Aligned with PECTAA 2026 Syllabus