Question

A short electric dipole has a moment of $16\times {10}^{-9}\text{Cm}$. The electric potential due to the dipole at a point at distance of $0.6\text{m}$ from the centre of the dipole, situates on a line making an angle of ${60}^{\circ }$ with the dipole axis is

• A. Zero
• B. $50\text{V}$
• C. $200\text{V}$
• D. $400\text{V}$

Answer 1

The correct option is C $200\text{V}$

Given dipole moment of short electric dipole,

$|\overrightarrow{P}|=16\times {10}^{-9}\text{Cm}\text{distance}r=0.6\text{m}\text{and}\theta ={60}^{\circ }\Rightarrow \cos {60}^{\circ }=\frac{1}{2}$

Electric potential, $V=\frac{KP\cos \theta }{r^2}$

$V=\frac{9\times {10}^9\times 16\times {10}^{-9}\times \frac{1}{2}}{(0.6{)}^2}$

$=\frac{9\times 8}{36\times {10}^{-2}}=200\text{V}$


<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Hence, (c) is the correct answer.