Gujarati
Hindi
2. Electric Potential and Capacitance
easy

Find the potential $V$ of an electrostatic field $\vec E = a\left( {y\hat i + x\hat j} \right)$, where $a$ is a constant.

A

$axy + C$

B

$-axy + C$

C

$axy$

D

$-axy$

Solution

$\mathrm{E}=a(y i+x j)$

$\mathrm{V}_{2}-\mathrm{V}_{1}=-\int(\mathrm{ayd} \mathrm{x}+\mathrm{axd} \mathrm{y})$

Take $\mathrm{V}_{1}=\mathrm{C}$ and $\mathrm{V}_{2}=\mathrm{V} .$ Then

${\mathrm{V}=-\mathrm{a} \int(\mathrm{ydx}+\mathrm{xdy})+\mathrm{C}} $

${=-\mathrm{a} \int \mathrm{d}(\mathrm{yx})+\mathrm{C}=-\mathrm{axy}+\mathrm{C}}$

$\mathrm{O} \mathrm{R}$

Verify with $ \overrightarrow{\mathrm{E}}=-\nabla \mathrm{V}=-\left(\hat{i} \frac{\partial}{\partial \mathrm{x}}+\hat{j} \frac{\partial}{\partial \mathrm{y}}\right)(-\mathrm{axy}+\mathrm{C})$

$=a y \hat{i}+a x \hat{j}+0=a(y \hat{i}+x \hat{j})$

Standard 12
Physics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.