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Electrostatics

Potential energy

Derive the expression for the electric potential energy of a system of two point charges q₁ and q₂ separated by distance r. What is the significance of this energy?

LA

Hard

5 Marks

70% Confidence

Confidence Score

70%

Times Viewed

0

Max Marks

5

Hints

1.work done in assembling the charges
2.use formula W = q₁q₂/(4πε₀r)
3.units: joule

Answer Outline

1.Bring charge q1, then bring q2 from infinity
2.Work done = ∫ F dr = q₁q₂/(4πε₀r)
3.Thus potential energy U = q₁q₂/(4πε₀r)
4.Significance: stored energy due to configuration

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