Three point charges are located at the corners of an equilateral triangle as in the figure below. calculate the net electric force on the 7-nc charge.
Each sides are .5 m. (q1=7μc) (q2=2 μc) (q3= -4 μc)
f=k q1 q2 / r^2
The Attempt at a Solution
F12= 8.988x10^9 (7x10^-6)(2x10^-6) /.5^2= 0.5
F13=8.988x10^9 (7x10^-6)(4x10^-6) / .5^2 = 1.006656
F12y=.5sin60= (sqrt of 3)/4=.4330127019
sqrt of (.753328^2+(-2.883132508x10^-3)^2)=.7534N
tan-1(-2.88...x10^-3 / .753328)= -.22°
I don't know what i'm doing wrong, but the answers i'm gettin aren't correct. help. thanks!