Question

An electric dipole of moment $p$ is lying along a uniform electric field $E$. The work done in rotating the dipole by ${90}^o$ is:

• A. $pE$
• B. $\sqrt{2}pE$
• C. $\frac{pE}{2}$
• D. $2pE$

Answer 1

The correct option is A $pE$

$Workdone=\Delta pE$

$pE=-\overrightarrow{p}\overrightarrow{E}$

$p{E}_f=0$

$p{E}_i=-pE$

$\Delta pE=pE$