Two charged masses hanging on a string. Finding the angle with respect to the horizon

1. Jan 22, 2013

anban

1. The problem statement, all variables and given/known data

I have a problem as follows: "Two charges of identical mass hang from the same point by a thread of length l. One has charge q and the other has charge 2q. Find the angle each mass makes with the vertical."

Now, I got an answer and found that each mass will make the same angle with respect to the vertical. Is this true? When I imagine this scenario in my head it seems like their angles would be different. Are the angles equal for both masses when the masses are equal, regardless of the charges?

2. Relevant equations

3. The attempt at a solution

There is an assumption that the masses are "large" and the charges are "small".

2. Jan 22, 2013

Staff: Mentor

Re: Two charged masses hanging on a string. Finding the angle with respect to the hor

Ponder Newton's Third Law.

3. Jan 22, 2013

anban

Re: Two charged masses hanging on a string. Finding the angle with respect to the hor

Got it- equal and opposite forces. Thank you.