Relatively simple vectors question, but no numbers....

[Bagwan]

The unit right now is electrostatics, but this question is really just vectors, nothing to do with charges or anything... anyways here is the info:

1. Homework Statement
Three identical point charges, A, B, and C are located as shown here:

The force A-on-C is the same as the force B-on-C. What is the net force on C?

Homework Equations

I think the only equation I need is the superposition of force principle:
F_netC = F_AonC + F_BonC

The Attempt at a Solution

[/B]
Breaking into components (not allowed to use cosine law for some reason):

I know X-axis force is 0 as the 2 forces cancel out (since they are both equal and in opposite directions).

F_netCY = F_AonC * cos(45) + F_BonC * cos(45)

Not sure what else I can do though...

EDIT: I messed around with the 1-1-sqrt(2) triangle and I'm not sure if this is right, but is (2/sqrt(2)) * F_AonC the right answer?

EDIT 2: Yes, that's the right answer, but sqrt(2) * F_AonC is also right.

Because guess what, 2 divided by squareroot(2) is THE SAME THING AS squareroot(2)...

 

[rpthomps]

seems okay to me

 

[rpthomps]

assuming the charges on the charges on the corners A and B are all the same polarity

 

[Bagwan]

assuming the charges on the charges on the corners A and B are all the same polarity

Yeah they are all identical.

seems okay to me

How would I use the 1-1-squareroot2 triangle to simplify it more? I'm not sure how to do that part too well.

 

[rpthomps]

replace your cos45 statement with the equivalent ratio