MCQ on Electromagnetism – I

Electric field lines: a) Always start from negative charges and end at positive charges. b) Can intersect each other in a region of space. c) Indicate the direction of the force on a positive test charge. d) Are denser in regions of weaker electric field.

• Always start from negative charges and end at positive charges.

• Can intersect each other in a region of space.

• Indicate the direction of the force on a positive test charge.

• Are denser in regions of weaker electric field.

Gauss's Law states that the total electric flux through a closed surface is proportional to: a) The total charge enclosed by the surface. b) The electric field at any point on the surface. c) The surface area of the closed surface. d) The permittivity of free space.

• The total charge enclosed by the surface.

• The electric field at any point on the surface.

• The surface area of the closed surface.

• The permittivity of free space.

The electric field due to an infinitely long, uniformly charged wire at a distance 'r' from the wire is proportional to: a) r b) 1/r² c) 1/r d) r²

• r

• 1/r²

• 1/r

• r²

Inside a solid conducting sphere in electrostatic equilibrium, the electric field is: a) Maximum at the center. b) Non-zero and uniform. c) Zero. d) Directed radially outwards.

• Maximum at the center.

• Non-zero and uniform.

• Zero.

• Directed radially outwards.

The electric field just outside the surface of a uniformly charged insulating sphere of radius R and total charge Q is: a) Zero. b) Q / (4πε₀R²). c) Q / (ε₀R). d) Dependent on the material of the sphere.

• Zero.

• Q / (4πε₀R²).

• Q / (ε₀R).

• Dependent on the material of the sphere.

Consider two parallel conducting plates with equal and opposite charges. The electric field between the plates is: a) Zero. b) Non-uniform and directed towards the positively charged plate. c) Uniform and directed from the positively charged plate to the negatively charged plate. d) Dependent on the distance from the plates.

• Zero.

• Non-uniform and directed towards the positively charged plate.

• Uniform and directed from the positively charged plate to the negatively charged plate.

• Dependent on the distance from the plates.

For a Gaussian surface enclosing a net positive charge, the electric flux through the surface will be: a) Zero. b) Negative. c) Positive. d) Dependent on the shape of the Gaussian surface.

• Zero.

• Negative.

• Positive.

• Dependent on the shape of the Gaussian surface.

The electric field inside a uniformly charged insulating sphere: a) Is zero. b) Is constant and non-zero. c) Increases linearly with the distance from the center. d) Decreases linearly with the distance from the center.

• Is zero.

• Is constant and non-zero.

• Increases linearly with the distance from the center.

• Decreases linearly with the distance from the center.

The surface charge density on a conducting sphere in electrostatic equilibrium is: a) Uniformly distributed over the surface. b) Higher at the points with smaller radius of curvature. c) Zero at all points. d) Dependent on the material of the sphere.

• Uniformly distributed over the surface.

• Higher at the points with smaller radius of curvature.

• Zero at all points.

• Dependent on the material of the sphere.

If a Gaussian surface encloses no net charge, the electric flux through the surface is: a) Maximum. b) Non-zero. c) Zero. d) Dependent on the electric field outside the surface.

• Maximum.

• Non-zero.

• Zero.

• Dependent on the electric field outside the surface.