Answer to Question #169685 in Field Theory for Himel

Question

Three charges are sitting at the corners of an equilateral triangle. If 𝑞1 = 𝑞3 = 10 𝜇𝐶 , 𝑞2 = 5 𝜇𝐶 and the length of each side is 20 cm, find the force experienced by charge 𝑞2 in unit-vector notation and magnitude-angle notation.

Answer 1

$$F_x=0\ N\\F=F_y=2F'\sin{60} \\F=F_y=2(9\cdot10^9)\frac{(10\cdot10^{-6})(5\cdot10^{-6})}{0.2^2}\sin{60}=19.5\ N$$

$$\vec{F}=19.5\ N \vec{j}\\ \vec{F}=19.5\ N \text{ 90}\degree$$