A molecule of a substance has a permanent electric dipole moment of magnitude 
. A mole of this substance is polarised (at low temperature) by applying a strong electrostatic field of magnitude 
. The direction of the field is suddenly changed from an angle of 
to 
. Estimate the heat released from the substance in aligning its dipoles along the new direction of the field.
Text Solution
Verified by ExpertsB
Given, dipole moment of each molecule 
and number of molecules in 1 mole of the substance 
.
Therefore, total dipole moment of all molecules,
Initial potential energy,
Final potential energy (when 
),
[finally 
and 
are aligned in the same direction]
Change in potential energy 
So, there is a loss in potential energy. This must be the energy released by the substances in the form of heat in aligning its dipole.
Heat energy 
Prepare Smarter with CGP Edu
Get practice questions, solutions, and test series in one place.
Write a Review
Share your experience with this question and solution.
Commentary
Send your comment, doubt, correction, or feedback to admin.
Similar Questions
Explore conceptually related problems