Question

Electric potential at any point is $V=-5x+3y+\sqrt{15}z$, then the magnitude of the electric field is :

• A. $3\sqrt{2}$
• B. $4\sqrt{2}$
• C. $5\sqrt{2}$
• D. $7$

Answer 1

Answer: (D)

$7$

Electric potential at point is $V=-5x+3y+\sqrt{15}z$
Electric field is $\overrightarrow{E}=-\nabla V=-(\hat{i}\frac{\partial }{\partial x}+\hat{j}\frac{\partial }{\partial y}+\hat{k}\frac{\partial }{\partial z})(-5x+3y+\sqrt{15}z)=-(-5\hat{i}+3\hat{j}+\sqrt{15}\hat{k})$
$|\overrightarrow{E}|$=7