Question

How can I solve the following statement?

What is the magnitude of the electric field at a point midway between a −8.3μC and a +7.8μC charge 9.2cm apart? Assume no other charges are nearby.

Answer 1

The net electric field at the midpoint is 6.85 x 10^7 N/C.

Step-by-step explanation:

q = − 8.3 μC

q' = + 7.8 μC

d = 9.2 cm

d/2 = 4.6 cm

The electric field due to the charge q at midpoint is

`E = (k q)/(r^2)\\\\E = (9* 10^9* 8.3* 10^(-6))/(0.046^2)\\\\E = 3.53* 10^7 N/C` leftwards

The electric field due to the charge q' at midpoint is

`E' = (k q)/(r^2)\\\\E' = (9* 10^9* 7.8* 10^(-6))/(0.046^2)\\\\E' = 3.32* 10^7 N/C`

The resultant electric field at mid point is

E'' = E + E' = (3.53 + 3.32) x 10^7 = 6.85 x 10^7 N/C