A plane wave front AB propagating from denser medium (1)into a rarer medium (2) is incident on the surface `P_1P_2` separating the two media as shown in the figure.
Using Huygen's principle, draw the secondary wavelets and obtain the refracted wave front in the diagram.

For a ray of light travelling from a denser medium of refractive index mu_1 to a rarer medium of refractive index mu_2 ,prove that (mu_2)/(mu_1) = sin C , where C is the critical angle of incidence for the media.

For a spherical surface,when refraction takes place from a rarer medium (mu_1) to a denser medium (mu_2) , we write -(mu_1)/u + (mu_2)/v = ( mu_2-mu_1)/R where the symbols have their usual meanings. Now suppose that the object is placed in the denser to the rarer medium . Then, rewrite the above equation.

State the principle,which helps us to determine the shape of the wavefront at a later time from its given shape at any time.Apply this principle to Derive Snell's law of refraction by drwing the refracted wavefront corresponing to a plane wavefront incident on the boundary separating a rarer medium from a denser medium.

A parallel plate capacitor with air as medium between the plates has a capacitance of 10 muF. The area of capacitor is divided into two equal halves and filled with two media as shown in the figure having dielectric constnt k_(1) = 2 and k_(2) = 4 . the capacitance of the system will now be

An object is placed 21 cm in front of a concave mirror of radius of curvature 10 cm.A glass slab of thickness 3 cm and refractive index 1.5 is then placed close to the irror in the space between the object and mirror as shown in Fig.2.62.Find the position of the final image formed.You may take the distacne of the near surface of the slab from the mirror to be 1 cm. .

A vessel ABCD of 10 cm width has two small slits S_(1) and S_(2) sealed with idebtical glass plates of equal thickness. The distance between the slits is 0.8 mm. POQ is the line perpendicular to the plane AB and passing through O, the middle point of S_(1) and S_(2) . A monochromatic light source is kept at S, 40 cm below P and 2 m from the vessel, to illuminate the slits as shown in the figure. Calculate the position of the central bright fringe on the other wall CD with respect of the line OQ. Now, a liquid is poured into the vessel and filled up to OQ. The central bright fringe is fiund to be at Q. Calculate the refractive index of the liquid.

How is a wavefront defined? Using Huygens' prniciple draw a figure showing the propagation of a plane wave refracting at a plane surface separating two media. Hence verify Snell's law of refraction.

How is a wavefront defined? Using Huygens' prniciple draw a figure showing the propagation of a plane wave reflecting at the interface of the two media. Show that the angle of incidence is equal to the angle of reflection.

A ocnvex refracting surface of radius of curvature 20 cm separeates two media of refractive indices 4//3 and 1.60.An object is placed in the first medium (mu=4//3) at a distance of 200 cm from the refractign surface.Calculate the position of the image formed.