An electric dipole of dipole moment 6 10-6 C m is placed in uniform electric field of magnitude 106 V/m. Initially, the dipole moment is parallel to electric field. The work that needs to be done on the dipole to make its dipole moment opposite to the field, will be J.
12
U = -pE
W = U(180 ) - U(0 ) = pE - (-pE) = 2pE
W = 2 6 10-6 106 = 12 J
Answer: 12
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