Torque on electric dipole placed in uniform electric field E is given as τ=pEsinθ.......(i) where, p= electric dipole moment and θ= angle measured with respect to direction of electric field. From Eq. (i), When θ=0∘⇒τ=pEsin0∘=0 When θ=
π
2
⇒τ=pEsin
π
2
=pE When θ=π⇒τ=pEsinπ=0 When θ=
3π
2
⇒τ=pEsin
3π
2
=−pE When θ=2π⇒τ=pEsin2π=0 Hence, graph between τ and θ is given as