Splung.com Physics Forum

[suzukits]

The following three point charges are placed on the x axis:

5 microcoulombs at x=0 ,

4 microcoulombs at x= - 40cm (B)

6 microcoulombs at x= 80cm.(A)

Find the force on A and B.

I really don't know how to use the formula for this.

[hepcj]

The electrostatic force on a charged particle is the sum of the forces on individual pairs of charges as given by Coulomb's Law:
Force on A:
F_A = Sum(i = charges 0 and B), q_A q_i/(4pi*epsilon_0* (r_A,i)^2)

Force on B:
F_B = Sum(i = charges 0 and A) q_B q_i/(4pi*epsilon_0 * (r_B,i)^2)


q_A is the charge on particle A , q_B is the charge on particle B and q_i is the charge on particle i.

where r_A,i is the distance between A and particle i,
similarly r_B,i is the distance between B and particle i.