Gauss’s Law

Gauss law may stated as

“The flux of electric field E throw any closed surface is 1/ℰ₀ times of total charge inclosed by the surface & if the surface does not inclose the charge the flux is equal to zero. i.e.

⨜E.dS=q/ℰ₀ (If q is inside the surface)

⨜E.dS=0        (If q is outside the surface)

Form of Fringes in Michelson Interferometer

The form of fringes depends on inclination of M₁ and M₂.Let M₂’ formed by reflection at the semi-silvered surface of G₁ so that AM₂’ equal to the interference fringes may be in regarded to be formed by light reflected from the surfaces of M₁ and M₂’.Thus the arrangement is equivalent to an air film inclosed between the reflecting surfaces M₁ and M₂’.

Field due to uniformly charged sphere

Application Of Gauss Law:-

(a)- Field outside the sphere:-

Suppose the charge q is uniformly distributed over a sphere of radius R as shown in figure.

Let us find the electric field E at the point P outside the sphere for which we draw a Gaussian surface shown by dotted curve at a concentric sphere of radius OP=r.

Michelson Interferometer

An interferometer is an instrument in which the phenomena of interference is used to make the precise measurement of wavelength or distances.