Q. The electric potential $V$ at any point $(x,y,z)$, all in meters in space is given by $V = 4x^{2}\ volt.$ The electric field at the point $(1,0,2)$ in $volt/meter$, is
A) 16 along positive $X$-axis
B) 8 along negative $X$-axis
C) 8 along positive $X$-axis
D) 16 along negative $X$-axis
Explanation
(b) $\overrightarrow{E} = - \frac{dV}{dx}\widehat{i} = - 8x\widehat{i}\ volt/meter$
$E_{(1,0,2)} = - 8\widehat{i}\ V/m$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.