1. Concept: In an electric dipole composed of equal and opposite charges, the midpoint behaves uniquely regarding scalar (potential) and vector (field) quantities.
2. Formula: $$ V_{net} = V_+ + V_- \quad \text{and} \quad \vec{E}_{net} = \vec{E}_+ + \vec{E}_- $$
3. Solution: - Potential is scalar. Since the distance to the positive charge equals the distance to the negative charge, their potentials sum algebraically to exactly zero: \( V_{net} = \frac{kq}{r} - \frac{kq}{r} = 0 \).
- Electric field is a vector. The positive charge pushes a positive test charge right. The negative charge pulls that same test charge right. The vectors constructively add together, meaning the total field is non-zero (\( E \neq 0 \)).
4. Why other options are incorrect: Option B assumes the fields cancel out (which only happens between two identical like-charges). Options C and D assume the scalar potential fails to cancel.
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