Question

What are the strength and direction of the electric field at the position indicated by the dot in the figure where q = 2.3 nC? Specify the direction as an angle above (positive) or below (negative) horizontal (the positive x-axis).

Magnitude      N/C
Direction      °

Answer 1

charge q = 2.3 nC, d= 8 cm = 0.08 m

we know that the field lines are radially away from a positive charge and

radially inward for the negative charge so the

electric fiedl strength at point dot is drawn in components

here the x component of electric field strenght of the charges cancel , because both are equal in mangitude and opposite in direction

the remaining is the y component , both are in the same direction that is in the -ve y direction

we know the electric field Ey = 2*kQ/r^2

Ey = (2*9*10^9*2.3*10^-9)/(sqrt(2)*0.08)^2 N/C

Ey = 3234.375 N/C

directed downward do it is Ey = -3234.375 N/C