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## Homework Statement

There are three point masses. 1 is fixed in space with the 2nd point mass directly below it on the ground. The 3rd point mass is an unknown distance to the right of mass number 2. These 3 point masses for a rt triangle with point 2 at the 90 degree angle. The vertical distance between point mass 1 and 2 is 1.5 m. The mass of each point mass is 5.5kg. Also there is kinetic friction between point mass 2 and the ground. All three point masses have a charge of +15 Coulombs. If mass 3 starts moving toward mass 2, how far away from 2 will 3 be when 2 starts to move?

## Homework Equations

F=MA

F=Eq

F=Qq/r^2

F=KQ/R^2

This problem seems to combine coulomb's law with with 2-d motion. However, I am stumped as to how to combine the 2 concepts. also, not knowing the original starting distance between 3 and 2 is complicating matters.

## The Attempt at a Solution

I am able to calculate the force that 1 exerts on 2 no problem but have no idea how to figure out the force that 3 exerts on 2. i also have no idea how to incorporate friction