• # question_answer The potential of the electric field produced by a point charge at any point$(x,y,z)$ is given by; $V=3{{x}^{2}}+5,$ where $x,\text{ }y,\text{ }z$are in metres and V is in volt. The intensity of the electric field at (-2, 1,0) is A)  $+17\,V{{m}^{-1}}$                    B) $-17\,V{{m}^{-1}}$C) $+12\,V{{m}^{-1}}$                     D) $-12\,V{{m}^{-1}}$

$V=3{{x}^{2}}+5$ $E=-\frac{dV}{dx}=-\frac{d}{dx}(3{{x}^{2}}+5)=-6x$ At $(-2,1,0),E=-6(-2)=12\,V/m.$ Hence, the correction option is [c].