Q. The potential of the electric field produced by point charge at any point $(x,y,z)$ is given by $V = 3x^{2} + 5,$ where $x,y$ are in metres and V is in volts. The intensity of the electric field at (-2,1,0) is
A) $+ 17\ Vm^{- 1}$
B) $- 17\ Vm^{- 1}$
C) $+ 12\ Vm^{- 1}$
D) $- 12\ Vm^{- 1}$
Explanation
(d) Potential $(V) = 3x^{2} + 5$
Intensity of the electric field=
$\frac{dV}{dx} = 6x$
$\therefore E\ at\ x = - 2$
$= 6( - 2) = - 12Vm^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.