Two equally charged balls, each of mass 0.10 gm, are suspended from the same point by threads 13 cm long. The balls come to rest 10 cm apart due to electrostatic repulsion. Determine the charge on each ball.

Answer 1

note 5 12 13 right triangle here

Fh = k Q1 Q2/d^2 horizontal electrostatic

Fd = m g gravity down

T = tension

T(12/13) = m g
T(5/13) = Fh

12 T = 13 m g
5 T = 13 Fh

12/5 = m g/Fh
Fh = (5/12) m g
so
9^10^9 Q^2/.1^2 = (5/12)(.0001)(9.8)
solve for Q

Answer 2

thats wrong