Q. An electric dipole of moment $\overrightarrow{p}$ is placed in a uniform electric field $\overrightarrow{E}$. Then (i) The torque on the dipole is $\overrightarrow{p} \times \overrightarrow{E}$ (ii) The potential energy of the system is $\overrightarrow{p}.\overrightarrow{E}$ (iii) The resultant force on the dipole is zero
A) (i), (ii) and (iii) are correct
B) (i) and (iii) are correct and (ii) is wrong
C) Only (i) is correct
D) (i) and (ii) are correct (iii) is wrong
Explanation
(b) In a uniform electric field $\overrightarrow{E},$ dipole experiences a torque $\overrightarrow{\tau}$ given by $\overrightarrow{\tau} = \overrightarrow{p} \times \overrightarrow{E}$ but experiences no force. The potential energy of the dipole in a uniform electric field $\overrightarrow{E}$ is $U = - \overrightarrow{p}.\overrightarrow{E}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.