Question Detail
Question
What is the electric field at a point P which is 30cm to the right of a point charge Q = -3.0μC?
Correct Answer
Option C is the correct answer.
Detailed Explanation
E = kQ/r² = (8.99×10⁹)(3×10⁻⁶)/(0.3)² ≈ 3×10⁵N/C, and since Q is negative, the field points toward the charge (toward Q), not away from it.
Hint
Compute the magnitude with E = kQ/r², then remember negative charges have field lines pointing inward, toward them.