Define poisson's ratio and mention the range of its theoretical values.

Define the optimal value.

Why poisson's ratio has no unit ?

Poisson's ratio is a _____.

What are different moduli of elasticity. Derive mathematical relation between them. Define poisson's ratio and prove that the limit lies between -1 to 1/2.

Define an electric dipole and mention the directions of electric field intensity.

Define dipole moment. Mention its formula.