A molecule of a substance has a permanent electric dipole moment of magnitude $10^{-31} Cm$. A mole of this substance is 100% polarised by applying a strong electrostatic field of magnitude $10^8 Vm^{-1}$. The direction of field is suddenly changed by an angle of 60°. Find the heat released by substance in aligning its dipoles along the new direction of the field.

[Take 1 mole = $6 × 10^{23}$ molecules]

3 J

The correct answer is Option (4) → 3J