Two 500 g spheres with equal positive charges are suspended by 10.0 cm long strings in a uniform electric field E = 2.00 x 106 N/C as shown.
a) If the charged spheres are in equilibrium when their strings make angles of 20.0. with the vertical, determine the charge on the spheres.
b) Determine the tension in the strings.
c) What would be the effect of reversing the direction of the electric field on the equilibrium position of the two spheres if they had equal negative charges?