# An electric field of 1000 V/m is applied to an electric dipole at angle of 45°. The value of electric dipole moment is 10−29 C.m. What is the potential energy of the electric dipole? a. − 9 × 10−20 J b. − 7 × 10−27 J c. − 10 × 10−29 J d. − 20 × 10−18 J

## Question ID - 50343 :- An electric field of 1000 V/m is applied to an electric dipole at angle of 45°. The value of electric dipole moment is 10−29 C.m. What is the potential energy of the electric dipole? a. − 9 × 10−20 J b. − 7 × 10−27 J c. − 10 × 10−29 J d. − 20 × 10−18 J

3537

Answer Key : (b) -

U = −

= −PE cos

= − (1029) (103) cos 45

= −0.707 x 1026 J

= − 7 x 1027 J.

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