Consider a small, conducting sphere of 0.0010 kg mass. Extra electrons are added to
this sphere and an identical sphere below it so that the excess charge on the top sphere is three times that on the lower one. How much extra charge would have to be placed upon the top sphere so that the electrical repulsion between the extra charge on these spheres would provide a force equal to the weight of the sphere when the spheres are 4.0 m apart?
a. 5.8 x 1012C
b. 2.4 x 106 C
c. 3.6 x 106 C
d. 7.2 x 106 C
e. none of these
this sphere and an identical sphere below it so that the excess charge on the top sphere is three times that on the lower one. How much extra charge would have to be placed upon the top sphere so that the electrical repulsion between the extra charge on these spheres would provide a force equal to the weight of the sphere when the spheres are 4.0 m apart?
a. 5.8 x 1012C
b. 2.4 x 106 C
c. 3.6 x 106 C
d. 7.2 x 106 C
e. none of these

[(9*10^9)*3*(q^2)]/16 = 0.0010*9.81or
q = sq rt[({9.81*16)/27}*10^12] C = 2.41*10^6 C So option "b. 2.4 x 106 C" is correct
q = sq rt[({9.81*16)/27}*10^12] C = 2.41*10^6 C So option "b. 2.4 x 106 C" is correct