Give Stokes formula and explain the symbols used.

Write down the expression for the Stoke's force and explain the symbols involved in it.

What do you understand by the scalar product of two vectors ? Write the formula, explaining the symbols used.

Write the formula for the lateral shift and explain the symbols used.

Write down lens maker’s formula using the symbols as used.

Write the formula for the equivalent focal length of two thin lenses separated by a small distance and explain the symbols used.