Electromagnetics – Multiple Choice Questions (MCQs)

1. 37. An equipotential surface is a surface where the electric potential is:

   • A. Zero
   • B. Constant
   • C. Varies linearly
   • D. Varies exponentially

2. 38. The unit of electric flux is:

   • A. Coulomb
   • B. Volt-meter
   • C. Newton-meter
   • D. Weber

3. 39. Which of the following describes a dielectric material?

   • A. Material with free electrons
   • B. Material that stores magnetic energy
   • C. Material that can be polarized
   • D. Material that conducts electricity very well

4. 40. The principle of superposition states that:

   • A. The total electric field is the sum of individual fields
   • B. The total magnetic field is the product of individual fields
   • C. Electric and magnetic fields are always independent
   • D. Fields only interact in a vacuum

5. 41. The electric potential at a point due to a point charge is given by:

   • A. kQ/r²
   • B. kQ/r
   • C. kQ
   • D. kQ²/r

6. 42. Which property of a material dictates its ability to store electric energy in an electric field?

   • A. Permeability
   • B. Permittivity
   • C. Conductivity
   • D. Resistivity

7. 43. The term 'retarded potentials' is used in the context of:

   • A. Static fields
   • B. Time-varying fields
   • C. DC circuits
   • D. AC circuits

8. 44. The concept of image charges is used to solve problems involving:

   • A. Symmetric charge distributions
   • B. Boundary conditions
   • C. Moving charges
   • D. Time-varying fields

9. 45. What is the SI unit of magnetic field intensity?

   • A. Ampere/meter
   • B. Tesla
   • C. Weber
   • D. Henry

10. 46. The inductance of a coil is a measure of its ability to:

    • A. Store electric energy
    • B. Store magnetic energy
    • C. Conduct electricity
    • D. Resist changes in voltage

11. 47. Which of the following is true for a perfect conductor?

    • A. ρv = 0
    • B. J = 0
    • C. E = 0 inside
    • D. B = 0 inside

12. 48. The Brewster angle is the angle at which:

    • A. Reflection is maximized
    • B. Transmission is maximized
    • C. Polarization occurs
    • D. No reflection occurs for a specific polarization