RBSE Solutions for Class 12 Physics Chapter 2: Electrostatic Potential and Capacitance

RBSE Class 12 Physics Chapter 2 syllabus, “Electrostatic Potential and Capacitance,” delves into the concepts of potential energy in an electrostatic field, electric potential, equipotential surfaces, and capacitors. Understanding this chapter is crucial, as it forms the basis of electrostatics and helps in understanding advanced concepts in physics.

Key Topics Covered in Chapter 2: Electrostatic Potential and Capacitance

Electrostatic Potential: Understanding the potential energy per unit charge in an electric field.
Potential Due to a Point Charge and System of Charges: Calculations for electric potential created by point charges and charge distributions.
Equipotential Surfaces: Characteristics and significance of surfaces on which electric potential remains constant.
Electric Potential Energy: Potential energy associated with charge configurations.
Capacitance and Capacitors: Introduction to capacitors, their working, and types.
Combination of Capacitors: Series and parallel combinations of capacitors.
Energy Stored in a Capacitor: Formula and derivation for the energy stored in a capacitor.

RBSE Solutions for Important Questions from Chapter 2

1. Define Electrostatic Potential and Explain Its Significance.

Solution: Electrostatic potential at a point in an electric field is the amount of work done to bring a unit positive charge from infinity to that point without acceleration. It is measured in volts (V) and is given by:

Significance:

Electrostatic potential helps in understanding the potential energy of charges in an electric field.
It is essential for calculating the electric potential energy in various configurations.

2. Calculate the Electrostatic Potential Due to a Point Charge.

Solution:

3. Explain Equipotential Surfaces and Their Properties.

Solution: Equipotential surfaces are surfaces where the electric potential remains constant at all points.

Properties of Equipotential Surfaces:

No work is required to move a charge on an equipotential surface.
Electric field lines are always perpendicular to equipotential surfaces.
For a point charge, equipotential surfaces are spherical shells centered on the charge.

4. What is a Capacitor? Explain Its Working and Use.

Solution: A capacitor is a device that stores electric charge and energy in an electric field. It consists of two conductive plates separated by an insulating material (dielectric). When a potential difference is applied, one plate accumulates positive charge, while the other accumulates negative charge, creating an electric field.

Uses:

Capacitors are used in electronic circuits for storing energy.
They are also used in filtering applications in power supplies and signal processing.

5. Define Capacitance and Derive Its Formula.

6. Derive the Expression for Energy Stored in a Capacitor.

7. Explain Series and Parallel Combination of Capacitors.

Preparation Tips for Chapter 2: Electrostatic Potential and Capacitance

Understand Core Concepts: Focus on understanding electrostatic potential, potential energy, and capacitance thoroughly.
Practice Derivations: Master derivations for potential due to a point charge, parallel plate capacitance, and energy stored in a capacitor.
Solve Numerical Problems: Practice numerical problems, especially those involving series and parallel combinations of capacitors and energy calculations.
Visualize Equipotential Surfaces: This will aid in solving conceptual questions about field directions and potential differences.

FAQs on Electrostatic Potential and Capacitance

What is the SI Unit of Capacitance?

The SI unit of capacitance is the Farad (F).

Why is No Work Done to Move a Charge on an Equipotential Surface?
- Since the electric potential is constant, there is no change in potential energy when moving along an equipotential surface, so no work is required.
What Happens When Capacitors are Connected in Parallel?
- When capacitors are connected in parallel, their capacitances add up, allowing them to store more charge collectively.
What is the Role of a Dielectric in a Capacitor?
- A dielectric increases the capacitance by reducing the effective electric field, allowing the capacitor to store more charge for a given potential difference.

With these RBSE solutions and preparation tips, students can gain a comprehensive understanding of “Electrostatic Potential and Capacitance,” enhancing their grasp of key concepts and problem-solving skills in electrostatics.