1. Concept: Electric potential is a scalar quantity, not a vector. To find total potential at a point, you simply add the algebraic values of the potentials from all nearby charges.
2. Formula: $$ V_{net} = V_+ + V_- $$
3. Solution: - At the exact midpoint, the distance to the positive charge is \( r \) and the distance to the negative charge is an identical \( r \).
- The positive charge creates a potential of \( V_+ = + \frac{kq}{r} \).
- The negative charge creates a potential of \( V_- = - \frac{kq}{r} \).
- Because they are identical in magnitude but opposite in sign, their algebraic sum evaluates to precisely \( 0 \text{ V} \).
4. Why other options are incorrect: If this question asked for Electric Field (a vector), the fields would reinforce and add together. But for Potential, opposite signs flawlessly cancel out.
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