Chapter 21, Problem 15P

GO The charges and coordinates of two charged particles held fixed in an xy plane are q₁ = +3.0 µC, x₁ = 3.5 cm. y₁ = 0.50 cm, and q₂ = −4.0 µC, x₂ = −2.0 cm, y₂ = 1.5 cm. Find the (a) magnitude and (b) direction of the electrostatic force on particle 2 due to particle 1. At what (c) x and (d) y coordinates should a third particle of charge q₃ = +4.0 µC be placed such that the net electrostatic force on particle 2 due to particles 1 and 3 is zero?