Question

Four point charges are located at the corners of a square. Each charge has magnitude 4.50 nC and the square has sides of length 2.80 cm. Find the magnitude of the electric field (in N/C) at the center of the square if all of the charges are positive and three of the charges are positive and one is negative.

Answer 1

Step-by-step explanation:

`r^2 = [(l)/(2)]^2 +[(l)/(2)]^2`

`r^2 = (2l^2)/(4)`

`r^2 =  (l^2)/(2)`

we know that electric field is given as

`E = (kq)/(r^2)`

from the figure electric field c and electric field a CANCEL OUT EACH OTHER

so, we have E_B and E_D is toward -q direction

`E_(net) = 2E = 2* (kq)/(r^2) =  (2kq)/(r^2)`

`E_(net) =(2kq)/(((l)/(2))^2)`

`E_(net) =(4kq)/(l^2)`

`E_(net) = (4*9*10^(9) *3.2*10^(-9))/((2*10^(-2))^2)`

`E_(net) = 28.8 *10^(-4) N/C`