Potential Energy of Dipole in Electric Field

AI Thread Summary
The discussion revolves around calculating the potential energy of a dipole in a uniform electric field. The dipole moment is given as 0.7 e * nm, and the electric field strength is 50000 N/C at an angle of 60 degrees. The equation used for potential energy is U = -pE cos(θ), leading to a calculated value of 2.8e-24 J. However, there is confusion regarding the correctness of this calculation, as the user has been informed that their answer is incorrect despite using the provided dipole moment. Clarification is sought on whether the dipole moment given should be directly applied in the potential energy formula.
peaceandlove
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Homework Statement


A dipole of moment 0.7 e * nm is placed in a uniform electric field with a magnitude of 50000 N/C. Find the potential energy of the dipole in the electric field at 60 degrees. Answer in units of J.


Homework Equations


-pE cos (theta)


The Attempt at a Solution


I found the magnitude of the torque on the dipole when it makes an angle of 60 degrees with the electric field to be 4.8497423e-24 N*m. (This I know to be correct.) I then used the equation -pE cos (theta) to get 2.8e-24 for the potential energy. However, I keep being told that this is incorrect.
 
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peaceandlove said:

Homework Statement


A dipole of moment 0.7 e * nm is placed in a uniform electric field with a magnitude of 50000 N/C. Find the potential energy of the dipole in the electric field at 60 degrees. Answer in units of J.

Homework Equations


-pE cos (theta)

The Attempt at a Solution


I found the magnitude of the torque on the dipole when it makes an angle of 60 degrees with the electric field to be 4.8497423e-24 N*m. (This I know to be correct.) I then used the equation -pE cos (theta) to get 2.8e-24 for the potential energy. However, I keep being told that this is incorrect.

Don't they give you the dipole moment p directly as a given "0.7 e * nm" ?

Isn't that the dipole moment you use in

U = -p*E*cosθ
 
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