PHYSICS electrode HELP?

Question

four 1.0 g spheres are dropped
(in a square shape, each 1cm from eachother to form the square, 1 sphere at each corner)

What is the speed of each sphere when they are very far apart?

each sphere is 10nC and positively charged

Answer 1

The speed of the spheres depends on when they were released and gravitation acceleration. Assuming that the air resistance is zero we have

v=gt
If on Earth we can assume g=9.81m/s