Question Detail
Question
A point charge, -30μC, is placed at the origin of the coordinates. Find the electric field at a point 50cm along the x-direction.
Correct Answer
Option C is the correct answer.
Detailed Explanation
E = kQ/r² = (8.99×10⁹)(30×10⁻⁶)/(0.5)² ≈ 1.08×10⁶N/C, and since the charge is negative, the field points toward the charge (negative sign).
Hint
Apply E = kQ/r² first for magnitude, then use the sign convention for a negative source charge.