# Force magnitude charges!

1. Jul 8, 2009

### talaroue

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

What is the force on the q1 charge? (a=3.41 cm, b=5.45 cm, q1=5.63 nC, q2=9.65 nC, q3=-5.93 nC.) Give your answer as a magnitude.

2. Relevant equations

F=K(q1q2/R^2)

3. The attempt at a solution

What am I doing wrong?

2. Jul 8, 2009

### rl.bhat

Angle between F2 and y-axis not 45 degrees.
Take the components of F2 on x-axis and y-axis.
Find the resultant of F1 and x component. Then find the resultant of this and y=component.

3. Jul 8, 2009

### talaroue

I am not sure what you mean. do you mean tan(theata)= F2/F1....?

4. Jul 9, 2009

### rl.bhat

tanθ =a/b where a is the distance between q1 and q3 and b is the distance between q2 and q3

5. Jul 9, 2009

### HallsofIvy

Staff Emeritus
You tell us that "a=3.41 cm, b=5.45 cm" but there is no "a" or "b" in your picture. I believe that rlbhat is assuming that that they are the x and y coordiantes of a2. Is that the case?