An electron is fixed at the origin as shown. What is the electric field at A?
(The coordinates are in metre)
The second thing we need to know is the distance of the charge from the point (where we want to find the field).
|→E|=14πε0|Q|r2⇒|→E|=14πε0×1.6×10−19(22)≈3.6×10−10 N/C
So, →E=−3.6×10−10 N/C ^i