Q2. Three point charges are arranged at the corners of a square of side as shown. What is the potential at the fourth corner (point A)?

Background

Topic: Electric Potential due to Point Charges

This question tests your understanding of how to calculate the electric potential at a point due to multiple point charges. The principle of superposition is used, where the total potential at a point is the algebraic sum of the potentials due to each charge.

Key Terms and Formulas

• Electric Potential due to a Point Charge:

• Superposition Principle:

• (Coulomb's constant)

• = charge, = distance from charge to point of interest

Step-by-Step Guidance

1. Identify the charges and their positions relative to point A. Label the charges as , , and note their distances to point A.

2. Calculate the distance from each charge to point A. For charges on the same side as A, the distance is . For the charge diagonally opposite A, use the Pythagorean theorem: .

3. Write the expression for the potential at point A due to each charge using , substituting the appropriate values for and for each charge.

4. Set up the total potential at point A as the sum of the potentials from all three charges. Do not combine or simplify yet; just write the sum.

Try solving on your own before revealing the answer!