Find the interaction force of two coils with magnetic moments \(p_{1 m}=4.0 \mathrm{~mA} \cdot \mathrm{m}^{2}\) and \(p_{2 m}=6.0 \mathrm{~mA} \cdot \mathrm{m}^{2}\) and collinear axes if the separation between the coils is equal to \(l=20 \mathrm{~cm}\) which exceeds considerably their linear dimensions