Question

In the example with an external field E = A/r², the interaction energy of q₁ = +7 μC with the external field at V(r₁) = 10⁷ V is:

Options

• 140 J

• 7 J

• 70 J

• 35 J

Answer 1

The interaction energy of a charge with the external field is q₁V(r₁) = (7 × 10⁻⁶ C) × (10⁷ V) = 70 J. This represents the potential energy of the positive charge in the external potential.