Physics - Electrostatics Question with Solution | TestHub

Consider an electric dipole with $-q$ charge at $A$ and $+q$ charge at $B$, placed along $z$-axis, such that its dipole moment is in negative $z$ direction. i.e., $p_{\mathrm{z}}=-10^{-7}\mathrm{Cm}$ The electric field is along positive direction of $z$-axis, such that $\frac{dE}{dz}=10^5{\mathrm{NC}}^{-1}{\mathrm{m}}^{-1}$ From, $F=qdE$ $=(q\times dz)\times \frac{dE}{dz}=p\frac{dE}{dz}$ Force experienced by the system in the negative $z$-direction, $F=-p\times \left(-\frac{dE}{dz}\right)=10^{-7}\times \left(-10^5\right)=-10^{-2}\mathrm{N}$