Calculate the amount of work done in rotating a dipole, of dipole moment 3 x 10-8cm, from its position of stable equilibrium to the position of unstable equilibrium, in a uniform electric field of intensity 104N/C.


Share with your friends
Call

P = 3 x 10-8cm ; E =104N/C 

At stable equilibrium (θ1 ) = 0° 

At unstable equilibrium (θ2) =180° 

Work done in rotating dipole is given by: 

W = PE (cosθ1 - cosθ2 )  

=  (3 x 10-8) (104) [cos0º - cos180º

= 3 x10-4 [1 - (- 1)] 

W = 6 x 10-8J