Electric field vector in component form

[miyayeah]

Homework Statement

A -12nC charge is located at (x,y) = (1.0cm, 0cm). What are the electric fields at the positions (x,y) = (5.0cm, 0cm), (-5.0cm, 0cm), and (0cm, 5.0cm)? Write each electric field vector in component form.

Homework Equations

E=k(q/r²)

The Attempt at a Solution

I was able to find the magnitude of the electric fields at the first two positions, but I am not sure how to find the last one. Also, how would you define the signs in this case for the first two electric fields? The answer for the first two were: -6.8x10⁴ i N/C, 3.0x10⁴ i N/C.

 

[Orodruin]

I was able to find the magnitude of the electric fields at the first two positions, but I am not sure how to find the last one.

Please show your work. What is the problem in finding the field strength for the last case in comparison to the previous two?

Also, how would you define the signs in this case for the first two electric fields?

For a negative charge, the field points towards the charge. For a positive charge, the field points away from the charge.

 

[Nguyen Son]

Like Mr. Oroduin said above, the field points towards the charge, but what's your problem here? Can you find distance from point (0cm;5cm) to the point charge?