Three small spheres with charge 2.00 mC are arranged in a line, with sphere 2 in the middle. Adjacent spheres are initially 8.0 cm apart. The spheres have masses m_1 = 20.0 g, m_2 = 85.0 g, and m_3 = 20.0 g. Their radii are much smaller than their separation. The three spheres are released from rest.
1. Find the acceleration of sphere 1 just after it is released?
2. What is the speed of sphere 1 when the spheres are far apart?
3. What is the speed of sphere 2 when the spheres are far apart?
4. What is the speed of sphere 3 when the spheres are far apart?
I understand that it is again a conservation of energy problem. I can calculate initial potential energy based on:
U = qV = qk(q_1/r_1 + q_2/r_1 + q_3/r_1)
I tried finding the electric field using this potential because of:
V = E*d with d = 0.08 m
Then I tried to find the Electrical force according to: F = q*E
Then I tried finding the acceleratoin given by: a = F/mass