Potential Energy of Dipole in Electric Field

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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