The work done for rotating a dipole is given by the change in the potential energy. The potential energy is given by
U=−p⋅E
W=ΔU=Uf−Ui
So, the work done is
W=−pEcos180∘−(−pEcos0∘)=2pE=2×6×10−6×1.5×103=18mJ
An electric dipole of dipole moment is 6.0×10−6Cm placed in a uniform electric field of 1.5×103NC−1 in such a way that dipole moment is along electric field. The work done in rotating dipole by 180∘in this field will be_______mJ.
Held on 8 Apr 2023 · Verified 6 Jul 2026.
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