Question

A point charge of -4.00 nC is at the origin, and a second point charge of 6.00 nC is on the x  axis at x = 0.810 m . Find the magnitude and direction of the electric field at each of the following points on the x axis.

A.x2 = 25.0 cm, E(x2)?

B.The field at point x2 is directed in(+x direction or -x direction)

C.x3 = 1.10 m, E(x3) ?

D. The field at point x3 is directed in ( +x direction or -x direction)

E.x4 = -20.0 cm, E(x4)?

F. The field at point x4 is directed in  ( +x direction or -x direction)

Answer 1

Let Q1= -4*10^-9 C; Q2=6*10^-9 C

A) Due to Q1: kQ1/(0.25)² = 576 N/C negative x axis

Due to Q2: kQ2/(0.81-0.25)² = 172.193 N/C negative x axis

net field: E= 748.193 N/C

B) in -ve x direction.

C) Due to Q1: kQ1/(1.1)² = 29.752 N/C negative x axis

Due to Q2: kQ2/(1.1-0.81)² = 642.092 N/C positive x axis

net field: E= 642.092 - 29.752 = 612.34 N/C

D) net field is directed towards positive x axis

E) Due to Q1: kQ1/(0.20)² = 900 N/C positive x axis

Due to Q2: kQ2/(0.81+0.20)² = 52.935 N/C negative x axis

net field: E= 847.065 N/C

F) directed in the positive x axis