Electromagnetism MCQ December 16, 2025June 28, 2024 by u930973931_answers 36 min Score: 0 Attempted: 0/36 Subscribe 1. What is the SI unit of magnetic flux density? (A) Henry (B) Ohm (C) Tesla (D) Volt 2. Which law describes the force between two electric charges? (A) Ampère’s Law (B) Ohm’s Law (C) Faraday’s Law (D) Coulomb’s Law 3. What is the value of the permittivity of free space (ε₀)? (A) 1.6 × 10⁻¹⁹ C (B) 8.85 × 10⁻¹² F/m (C) 9.8 m/s² (D) 3 × 10⁸ m/s 4. Which of the following statements about electric potential is true? (A) It is a vector quantity (B) It depends on the amount of charge only (C) It is a scalar quantity (D) It is not related to electric fields 5. What is the direction of the magnetic field around a straight current-carrying conductor? (A) Radial outward (B) Tangential to the conductor (C) Axial to the conductor (D) Spherical 6. Which law states that the induced electromotive force (emf) is equal to the negative rate of change of magnetic flux? (A) Faraday’s Law of Electromagnetic Induction (B) Ampère’s Law (C) Lenz’s Law (D) Gauss’s Law for Electricity 7. The SI unit of magnetic flux is: (A) Tesla (B) Henry (C) Weber (D) Ohm 8. What happens to the resistance of a conductor when its temperature increases? (A) Increases (B) Decreases (C) Remains the same (D) Depends on the material 9. What is the direction of the force on a charged particle moving in a magnetic field? (A) Perpendicular to both the magnetic field and motion (B) Opposite to the direction of motion (C) Parallel to the magnetic field (D) Along the direction of motion 10. What is the SI unit of electric current? (A) Ohm (B) Volt (C) Ampere (D) Weber 11. According to Lenz’s Law, the induced current flows: (A) In the same direction as motion (B) Parallel to the magnetic field (C) Randomly (D) In the opposite direction to the cause 12. Which of the following materials is ferromagnetic? (A) Copper (B) Iron (C) Aluminum (D) Silver 13. The electromagnetic spectrum includes: (A) Visible light (B) X-rays (C) All of the above (D) Radio waves 14. What type of electromagnetic waves are used in MRI scanners? (A) Radio waves (B) Microwaves (C) X-rays (D) Gamma rays 15. Which law relates electric field to the charge enclosed? (A) Ampère’s Law (B) Lenz’s Law (C) Faraday’s Law (D) Gauss’s Law for Electricity 16. The force on a current-carrying conductor in a magnetic field is given by: (A) F = ILBsinθ (B) F = qE (C) F = ma (D) F = kq₁q₂/r² 17. Which phenomenon is used in electric generators? (A) Newton’s Law (B) Ohm’s Law (C) Electromagnetic induction (D) Coulomb’s Law 18. When magnetic flux through a loop decreases, the induced current is: (A) Zero (B) Counterclockwise (C) Clockwise (D) Material dependent 19. The unit of magnetic pole strength is: (A) Coulomb (B) Weber (C) Ampere (D) Tesla 20. Magnetic field due to a long straight conductor is: (A) B = (4πr)/(μ₀I) (B) B = (μ₀I)/(4πr) (C) B = (2πr)/(μ₀I) (D) B = (μ₀I)/(2πr) 21. Which law explains the magnetic field produced by current? (A) Lenz’s Law (B) Faraday’s Law (C) Ampère’s Law (D) Coulomb’s Law 22. What happens to capacitance when plate separation increases? (A) Decreases (B) Increases (C) Remains constant (D) Depends on charge 23. Which of the following is not a vector quantity? (A) Electric field (B) Magnetic flux (C) Electric potential (D) Magnetic field 24. Which device measures electric current? (A) Ammeter (B) Voltmeter (C) Ohmmeter (D) Galvanometer 25. The right-hand rule determines: (A) Direction of current (B) Direction of potential (C) Direction of electric field (D) Direction of magnetic field 26. Which statement about ferromagnetic materials is true? (A) They repel magnetic fields (B) They retain magnetization (C) They magnetize weakly (D) They have low permeability 27. Electric field lines of a positive charge are: (A) Radially inward (B) Perpendicular (C) Tangential (D) Radially outward 28. Which law states emf is proportional to the rate of change of current? (A) Ampère’s Law (B) Faraday’s Law (C) Lenz’s Law (D) Ohm’s Law 29. A property of superconductors is: (A) High resistance (B) Zero resistance (C) Low permeability (D) High capacitance 30. Transformer cores are made of: (A) Iron (B) Silver (C) Copper (D) Aluminum 31. Magnetic flux is measured in: (A) Tesla (B) Weber (C) Ohm (D) Henry 32. Which law states current entering a junction equals current leaving it? (A) Coulomb’s Law (B) Kirchhoff’s Current Law (C) Faraday’s Law (D) Ampère’s Law 33. Lorentz force on a charge moving perpendicular to E and B fields is: (A) Along motion (B) Opposite to motion (C) Zero (D) Perpendicular to both fields 34. Inductance of a coil is associated with: (A) Magnetic flux (B) Current (C) Voltage (D) Resistance 35. Which law explains force between parallel current-carrying conductors? (A) Coulomb’s Law (B) Ohm’s Law (C) Lenz’s Law (D) Ampère’s Law 36. The magnetic field inside a current-carrying solenoid is: (A) Variable (B) Tangential (C) Radial (D) Along its axis