Finding magnitude of new electric fields

[wbetting]

Homework Statement

In Fig. 22-31 the four particles are fixed in place and have charges q1 = q2 = 3e, q3 = 2e, and q4 = -10e. Distance d = 5.42 μm. What is the magnitude of the net electric field at point P due to the particles?

Homework Equations

E=1/(4πε0) x [ q4/2d^2-q3/d^2] j

=1/(4πε0) X [(10q/4d)^2- (2q/d^2)

The Attempt at a Solution

my work is above and i got 1.53 x 10^20 which is wrong and i have no idea where i went wrong! i followed the student solution manual!

 

[tiny-tim]

hi wbetting!

(try using the X² and X₂ buttons just above the Reply box )

In Fig. 22-31 the four particles are fixed in place and have charges q1 = q2 = 3e, q3 = 2e, and q4 = -10e. Distance d = 5.42 μm. What is the magnitude of the net electric field at point P due to the particles?

Homework Equations

E=1/(4πε0) x [ q4/2d^2-q3/d^2] j

=1/(4πε0) X [(10q/4d)^2- (2q/d^2)

is this a square? where is P?

why is there no q₁ or q₂ in your equations?

and why do your equations look like scalar equations when the electric field is a vector?

show us your full calculations, and then we'll see what went wrong, and we'll know how to help! ​