# A substance of dipole moment $4 \times 10^{−8} C\; m$ is placed in an electric field of intensity E. When the direction of the field is changed by an angle of $30^{\circ}$, the heat released by the substance is $2.2\; J.$ What is the value of the electric field intensity E?

$(B) 1.88 \times 10^8 Vm^{-1}$