The potential energy (PE) of an electric dipole in a uniform electric field is given by the formula: PE=
→
−p
⋅
→
E
=−pEcosθ Let's evaluate the potential energy for different angles: (a) θ=180∘ : PE=−pEcos180∘=pE This corresponds to option (ii) in Column-II. (b) θ=120∘ : PE=−pEcos120∘=−pE(
−1
2
)=
pE
2
This corresponds to option (iii) in Column-II. (c) θ=90∘ : PE=−pEcos90∘=0 This corresponds to option (iv) in Column-II. Thus, the correct matching is: a⟶ (ii) b⟶ (iii) c⟶ (iv)