Chapter 1: Electric Charges and Fields for AHSEC Class 12 Physics

 Here are some probable questions from Chapter 1: Electric Charges and Fields for AHSEC Class 12 Physics, based on recent trends and previous years' papers:

Short Answer Type (1-2 Marks)

1. State and explain the principle of superposition of electric forces.
2. Define electric field intensity. What is its SI unit?
3. Define electric dipole moment. Write its SI unit.
4. State Gauss's law in electrostatics.
5. What is the physical significance of electric flux?
6. Write two properties of electric field lines.
7. What is meant by electrostatic shielding?
8. State the conditions for a charge distribution to be in equilibrium.
9. What is the effect of a dielectric medium on Coulomb’s force?
10. Define quantization of charge and state its mathematical expression.

Short Derivation/Numerical Type (3-4 Marks)

11. Derive the expression for the electric field due to a point charge.
12. Derive an expression for the torque acting on an electric dipole in a uniform electric field.
13. Prove that the total electric flux through a closed surface enclosing a charge is independent of the shape or size of the surface.
14. Derive an expression for the electric field at an axial point of an electric dipole.
15. Derive an expression for the electric field at a point on the equatorial line of a dipole.
16. Using Gauss’s law, derive an expression for the electric field due to a long straight charged wire.
17. Using Gauss’s law, derive an expression for the electric field due to a uniformly charged infinite plane sheet.
18. A charge of $2 \times 10^{-9} C$ is placed in vacuum. Calculate the electric field at a distance of 30 cm from the charge.
19. Two charges, +5μC and -5μC, are separated by 10 cm. Calculate the electric field at a point 5 cm away from the midpoint of the dipole along its axial line.
20. A square of side 10 cm has charges of +2μC, -2μC, +2μC, and -2μC placed at its four corners. Find the resultant electric field at the center.

Long Answer Type (5-6 Marks)

21. Derive an expression for the potential energy of an electric dipole in a uniform electric field.
22. Explain the concept of continuous charge distribution and derive an expression for the electric field due to a uniformly charged ring.
23. Derive an expression for the electric field due to a charged spherical shell at (i) a point outside the shell and (ii) a point inside the shell.
24. Explain the concept of electric flux and derive the relation between electric field and flux using Gauss’s law.
25. Explain how an electric field is defined using Gauss’s law for a uniformly charged spherical conductor.