Question

The torque induced on a dipole when placed in an electric field E is given by _________

(a) Esinθ

(b) pEsinθ

(c) Ecosθ

(d) pEcosθ

I had been asked this question by my school teacher while I was bunking the class.

This interesting question is from Dielectric Polarisation topic in section Dielectrics of Engineering Physics II

Answer 1

Right option is (b) pEsinθ

To elaborate: The torque on the dipole when it is placed in an electric field is given by: pEsinθ. It tends to align the dipole in the direction of the electric field.