📡 Chapter 18: Electromagnetic Induction & EM Waves – Multiple Choice 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 induced e.m.f., slip rings in A.C. generators, sky color, photons, and transformers. Each MCQ is presented with the correct answer and detailed explanation 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 18
Electromagnetic Induction covers Faraday's law, Lenz's law, A.C. generators, transformers, cathode rays, CRO, and EM waves.
📖 Multiple Choice Questions (PECTAA 2026)
18.1 What happens to the induced e.m.f. in a coil if the rate of change of the magnetic field increases?
✅ Correct Answer: (C) Increases
According to Faraday's law, induced e.m.f. is directly proportional to the rate of change of magnetic flux, so a faster change produces a larger induced e.m.f.
According to Faraday's law, induced e.m.f. is directly proportional to the rate of change of magnetic flux, so a faster change produces a larger induced e.m.f.
18.2 In an A.C generator, slip rings are used to:
✅ Correct Answer: (A) reverse current direction periodically
Slip rings allow the current direction to reverse naturally with each half-turn of the coil, producing alternating current.
Slip rings allow the current direction to reverse naturally with each half-turn of the coil, producing alternating current.
18.3 The sky appears blue during the day due to:
✅ Correct Answer: (B) scattering of shorter wavelengths
Blue light has a shorter wavelength and scatters more easily than other colours when sunlight passes through the atmosphere.
Blue light has a shorter wavelength and scatters more easily than other colours when sunlight passes through the atmosphere.
18.4 Light can be considered as massless particles called:
✅ Correct Answer: (C) photons
According to modern physics, light is made up of massless particles called photons that carry energy and momentum.
According to modern physics, light is made up of massless particles called photons that carry energy and momentum.
18.5 In a transformer, energy is transferred from the primary coil to the secondary coil through:
✅ Correct Answer: (B) a magnetic field in the iron core
The iron core channels the changing magnetic field from the primary coil to the secondary coil, transferring energy without direct electrical connection.
The iron core channels the changing magnetic field from the primary coil to the secondary coil, transferring energy without direct electrical connection.
📡 Key Concepts – Electromagnetic Induction & EM Waves
Faraday's Law: \(\epsilon = -N \frac{\Delta \phi}{\Delta t}\)
Transformer Turns Ratio: \(\frac{V_s}{V_p} = \frac{N_s}{N_p}\)
Magnetic Flux: \(\phi = BA \cos \theta\)
Photons: Massless particles of light that carry energy and momentum.
Unit 10Thermal Physics
Unit 11Transfer of Thermal Energy
Unit 12Waves
Unit 13Sound
Unit 14Light
Unit 15Electrostatics
Unit 16Electricity
Unit 17Electromagnetism
Unit 18✨ Electromagnetic 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, read each question carefully and eliminate obviously wrong options. These MCQs follow the PECTAA 2026 pattern and are prepared by Subject Specialist Muhammad Tayyab.
Created by Hira Science Academy | Aligned with PECTAA 2026 Syllabus