Introduction
Electromagnetism is an important chapter of Class 10 Physics that explains the relationship between electricity and magnetism. This chapter introduces students to magnetic effects of electric current, electromagnets, electromagnetic induction, electric motors, generators, and transformers. Understanding electromagnetism helps explain how many electrical devices and modern technologies work.
Students learn how a current-carrying conductor produces a magnetic field and how a changing magnetic field can produce electric current. The chapter also explains important principles such as Faraday’s laws of electromagnetic induction, Fleming’s left-hand rule, Fleming’s right-hand rule, and the working of devices that convert energy from one form to another. Applications such as electric bells, motors, generators, and power transmission systems show the importance of electromagnetism in everyday life.
On this page, you will find carefully selected Class 10 Physics Chapter 6 Electromagnetism MCQs with answers and explanations, along with learning outcomes, quick revision notes, important definitions, formulas, exam tips, and common mistakes to help you prepare effectively for school and board examinations.
Learning Outcomes
After studying this chapter, students will be able to:
- Explain the magnetic effect of electric current.
- Describe the working of electromagnets.
- Apply the right-hand grip rule.
- Understand electromagnetic induction.
- Explain Faraday’s laws of electromagnetic induction.
- Differentiate between motors and generators.
- Describe the working principle of transformers.
- Identify practical applications of electromagnetism.
Quick Notes – Chapter Summary
- A current-carrying conductor produces a magnetic field around it.
- Oersted discovered the magnetic effect of electric current.
- The right-hand grip rule shows the direction of magnetic field around a conductor.
- An electromagnet is made by passing current through a coil wound around a soft iron core.
- Electromagnetic induction produces emf due to changing magnetic flux.
- Faraday’s laws explain the production of induced emf.
- Fleming’s left-hand rule is used for electric motors.
- Fleming’s right-hand rule is used for generators.
- Electric motors convert electrical energy into mechanical energy.
- Generators convert mechanical energy into electrical energy.
- Transformers change AC voltage levels.
- Step-up transformers increase voltage, while step-down transformers decrease voltage.
Important Definitions
Electromagnetism: The study of the relationship between electricity and magnetism.
Magnetic Field: The region around a magnet or current-carrying conductor where magnetic force acts.
Electromagnet: A temporary magnet produced by electric current flowing through a coil.
Electromagnetic Induction: The process of producing emf due to a changing magnetic field.
Induced Current: Electric current produced due to electromagnetic induction.
Electric Motor: A device that converts electrical energy into mechanical energy.
Generator: A device that converts mechanical energy into electrical energy.
Transformer: A device used to increase or decrease AC voltage.
Magnetic Flux: The total magnetic field passing through a given area.
Important Formulas
Transformer Equation
Vp / Vs = Np / Ns
- Where:
- Vp = Primary voltage
- Vs = Secondary voltage
- Np = Number of turns in primary coil
- Ns = Number of turns in secondary coil
Faraday’s Law
Induced emf ∝ Rate of change of magnetic flux
- or
ε ∝ ΔΦ / Δt
- Where:
- ε = Induced emf
- Φ = Magnetic flux
- t = Time
Important Concepts
Power transmission.
Magnetic effect of current.
Electromagnets.
Right-hand grip rule.
Fleming’s left-hand rule.
Fleming’s right-hand rule.
Electromagnetic induction.
Electric motors.
Generators.
Transformers.
Class 10 Physics Chapter 6 – Electromagnetism MCQs
1. Which scientist discovered the magnetic effect of electric current?
- A. Oersted ✅
- B. Faraday
- C. Ampere
- D. Maxwell
Explanation: In 1820, Oersted discovered that a current-carrying conductor produces a magnetic field around it.
2. The right-hand grip rule is used to find:
- A. Direction of magnetic field around a current-carrying wire ✅
- B. Direction of current in a generator
- C. Direction of force on a conductor
- D. Direction of electric field
Explanation: The right-hand grip rule relates the thumb to current direction and fingers to magnetic field direction.
3. Electromagnets are made by:
- A. Passing current through a coil wound around a soft iron core ✅
- B. Using a permanent magnet
- C. Using copper plates
- D. Charging a capacitor
Explanation: Soft iron enhances the magnetic field when current flows through the surrounding coil.
4. Faraday’s first law of electromagnetic induction states that:
- A. A changing magnetic field induces an emf ✅
- B. Current produces a magnetic field
- C. Magnetic poles exist in pairs
- D. Electric charge is conserved
Explanation: Faraday found that a changing magnetic flux through a circuit induces an electromotive force (emf).
5. Fleming’s left-hand rule is used to find:
- A. Direction of force on a current-carrying conductor in a magnetic field ✅
- B. Direction of induced current
- C. Magnetic polarity
- D. Electric potential
Explanation: Fleming’s left-hand rule relates the directions of current, magnetic field, and force.
6. Fleming’s right-hand rule is applied to:
- A. Find direction of induced current ✅
- B. Find direction of force
- C. Find magnetic field direction
- D. Find electric potential
Explanation: The right-hand rule is used for generators to find induced current direction.
7. The working principle of an electric motor is based on:
- A. Force on a current-carrying conductor in a magnetic field ✅
- B. Induction of emf
- C. Electrostatics
- D. Heating effect of current
Explanation: Motors convert electrical energy into mechanical energy using this principle.
8. The device used to convert mechanical energy into electrical energy is:
- A. Generator ✅
- B. Motor
- C. Transformer
- D. Electromagnet
Explanation: Generators use electromagnetic induction to produce electricity from mechanical rotation.
9. Which core material is preferred for transformers?
- A. Soft iron ✅
- B. Steel
- C. Copper
- D. Aluminium
Explanation: Soft iron has high magnetic permeability and low hysteresis loss, ideal for transformers.
10. Step-up transformers increase:
- A. Voltage ✅
- B. Current
- C. Resistance
- D. Power
Explanation: Step-up transformers increase voltage while decreasing current.
11. The SI unit of magnetic flux is:
- A. Weber ✅
- B. Tesla
- C. Henry
- D. Gauss
Explanation: Magnetic flux is measured in webers (Wb).
12. Which rule determines the polarity of an electromagnet?
- A. Right-hand grip rule ✅
- B. Fleming’s left-hand rule
- C. Maxwell’s rule
- D. Ampere’s rule
Explanation: The right-hand grip rule helps find the north and south poles of an electromagnet.
13. Which effect of current is used in electric bells?
- A. Magnetic effect ✅
- B. Heating effect
- C. Chemical effect
- D. Optical effect
Explanation: Electric bells work by attracting a metal striker using an electromagnet.
14. Faraday’s second law states that induced emf is proportional to:
- A. Rate of change of magnetic flux ✅
- B. Magnetic pole strength
- C. Number of field lines
- D. Direction of field
Explanation: The faster the magnetic flux changes, the greater the induced emf.
15. Which device changes AC voltage levels?
- A. Transformer ✅
- B. Generator
- C. Motor
- D. Rectifier
Explanation: Transformers step voltage up or down using electromagnetic induction.
16. A step-down transformer is used to:
- A. Increase voltage
- B. Decrease voltage ✅
- C. Convert AC into DC
- D. Store electric charge
Explanation: A step-down transformer reduces AC voltage while increasing current.
17. The phenomenon responsible for the working of generators is:
- A. Electrostatic induction
- B. Heating effect of current
- C. Electromagnetic induction ✅
- D. Chemical effect of current
Explanation: Generators produce electricity by electromagnetic induction.
18. Increasing the number of turns in an electromagnet coil will:
- A. Increase magnetic strength ✅
- B. Remove magnetism
- C. Stop current flow
- D. Reduce voltage to zero
Explanation: More turns in the coil increase the strength of the magnetic field produced.
19. Which current type is required for transformer operation?
- A. Direct current only
- B. Alternating current ✅
- C. Static electricity
- D. No current is required
Explanation: Transformers require changing magnetic fields produced by alternating current.
20. The purpose of using high voltage in power transmission is to:
- A. Increase resistance
- B. Reduce frequency
- C. Reduce power loss ✅
- D. Stop electromagnetic induction
Explanation: High voltage transmission reduces current, which decreases energy losses in power lines.
Exam Tips
- Learn the difference between motors and generators.
- Remember Fleming’s left-hand and right-hand rules.
- Understand Faraday’s laws instead of only memorizing them.
- Revise transformer equations and voltage changes.
- Learn practical uses of electromagnets.
Common Mistakes
❌ Confusing electric motors with generators.
❌ Mixing Fleming’s left-hand and right-hand rules.
❌ Thinking transformers work with DC current.
❌ Forgetting that changing magnetic fields produce induced emf.
❌ Confusing step-up and step-down transformers.
Conclusion
Electromagnetism explains the connection between electric currents and magnetic fields. Concepts such as electromagnetic induction, electromagnets, motors, generators, and transformers are essential for understanding modern electrical technology. Learning these principles helps students understand power generation, transmission systems, and everyday electrical devices. Regular practice of MCQs, formulas, and key concepts will improve understanding and examination performance.