An electric field of 1000 V/m is applied to an electric dipole at angle of 45o. The value of electric dipole moment is 10–29 C.m. What is the potential energy of the electric dipole?
- 7 $$ \times $$ 10–27 J
$$-$$ 9 $$ \times $$ 10–20 J
$$-$$ 10 $$ \times $$ 10–29 J
$$-$$ 20 $$ \times $$ 10–18 J
U = $$-$$ $$\overrightarrow P .\overrightarrow E $$
= $$-$$ PE cos $$\theta $$
= $$-$$ (10$$-$$29) (103) cos 45o
= $$-$$ 0.707 $$ \times $$ 10$$-$$26 J
= $$-$$ 7 $$ \times $$ 10$$-$$27 J.
MCQ (Single Correct Answer)
JEE Main 2019 (Online) 11th January Evening Slot
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