Electric Potential

Electric potential is one of the most powerful concepts in electrostatics. While electric field strength tells you about the force a charge would experience, electric potential tells you about the energy landscape — how much work would be done in moving a charge from one place to another.

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Electric Potential at a Point

The electric potential V at a point in a field is defined as the work done per unit positive charge in bringing a small test charge from infinity to that point.

For a point charge Q, the electric potential at a distance r is:

V = kQ / r = Q / (4πε₀r)

where k = 8.99 × 10⁹ N m² C⁻².

Key Features

• Potential is a scalar quantity (not a vector) — it has magnitude and sign but no direction
• A positive charge creates positive potential that decreases with distance
• A negative charge creates negative potential that becomes more negative closer to the charge
• At infinity, V = 0 by convention
• The unit of potential is the volt (V), where 1 V = 1 J C⁻¹