Chapter 23, Problem 23.17E

Point charges q₁ = + 2.00 μC and q₂ = −2.00 μC are placed at adjacent corners of a square for which the length of each side is 3.00 cm. Point a is at the center of the square, and point b is at the empty corner closest to q₂. Take the electric potential to be zero at a distance far from both charges. (a) What is the electric potential at point a due to q₁ and q₂. (b) What is the electric potential at point b? (c) A point charge q₃ = −5.00 μC moves from point a to point b. How much work is done on q₃ by the electric forces exerted by q₁ and q₂? Is this work positive or negative?