Question
The potential function of an electrostatic field is given by $V = 2x^2$. Determine the electric field strength at the point $(2\,m, 0, 3\,m)$
✓
Answer
$\mathrm{E}=-\frac{\mathrm{dV}}{\mathrm{dx}}=-(4 \mathrm{x}) \hat{\mathrm{i}}$
$\mathrm{E}=-4(2)=-8 \hat{\mathrm{i}}$
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