Problem 3. y, Two equal positive charges are on the y axis, one at y = +a and the other at y = a as illustrated above. The +a 0C1 electric field at the origin is zero. A positive test charge +qo placed at the origin will therefore be in equilibrium (Ftot = 0 on (10). %o a) Find expression for the total force acting on go at po- sitions (as, 0) and (0, y) (points on the a: and y axes) when 9: