Question

Object A, which has been charged to + 12 nC , is at the origin. Object B, which has been charged to − 20 nC , is at (x,y)=(0.0cm,2.0cm). What is the magnitude of the electric force on object A? What is the magnitude of the electric force on object B?

Answer 1

G_a= +12nC = +12*10^-9C

G_b= - 20 nC = -20*10^-9C

part (A)

the magnitude of the electricity force on object A is :

            F_e= k*GaGb / r²

                 =9*10⁹* 12*10^-9 * 20*10^-9 / (2*10^-2)^2

                   = 2160*10^-9/4*10^-4

                     = 540*10^-5c

                             = 5.40*10^-3c

part (B)

the magnitude of the electricity force on B is same as that b of A.