Coulomb's law for the magnitude of the force Fbetween two particles with charges Q and Q′separated by a distance d is

|F|=K|QQ′|d2,

where K=14πϵ0, and ϵ0=8.854×10−12C2/(N⋅m2) is the permittivity of free space.

Consider two point charges located on the x axis: one charge, q1 = -15.0 nC , is located atx1 = -1.715 m ; the second charge,q2 = 32.5 nC , is at the origin (x=0.0000).