Question

The electric field and the potential of an electric dipole vary with distance r as

• A. $ \frac{ 1}{ r} $ and $\frac{ 1}{ r^2 } $
• B. $ \frac{ 1}{ r^2} $ and $ \frac{ 1}{ r } $
• C. $ \frac{ 1}{ r^2} $ and $ \frac{ 1}{ r^3 } $
• D. $ \frac{ 1}{ r^3} $ and $ \frac{ 1}{ r^2 } $

Answer 1

Answer: (D)

Electric fieid and eiectric potential at a general point at a distance r from the centre of the dipoie is
$ E_g = \frac{ 1}{ 4 \pi \varepsilon_0 } \frac{ P}{ r^3 } \sqrt{ ( 3 \, cos^2 \, \theta + 1) }$
and $ V_g = \frac{ 1}{ 4 \pi \varepsilon_0 } \frac{ p \, cos \, \theta }{ r^2 }$