Optics Answers

A small object is placed 20 cm in front of a block of glass 10 cm thick and its farther side silvered.The image is formed 22 cm behind the silvered face.Find the refractive index of glass.
Options are
(a) 1.15
(b) 1.25
(c) 1.67
(d) 1.1

calculate the wavelength at which the energy of a photon becomes equal to the average thermal energy of atoms in a solid at room temperature.

An isosceles prism of angle 120° has a refractive index 1.44. Two parallelmonochromatic rays enter the prism parallel to each other in air as shown. The rays emerge from the opposite face-
(A) are parallel to each other
(B) are diverging
(C) make an angle 2 [sin−1(0.72) − 30°] with each other
(D) make an angle 2 sin −1(0.72) with each other

A convex spherical refracting surface with radius R separates a medium having refractive index 5/2 from air.An object is moved towards the surface from far away from the surface along the central axis,its image-
a) changes from real to virtual when it is at a distance R from the surface.
b) changes from virtual to real when it is at a distance R from the surface.
c) changes from real to virtual when it is at a distance 2R/3 from the surface.
d) changes from virtual to real when it is at a distance 2R/3 from the surface.

Find the smallest size looking glass which a man with a face 24cm*16cm should purchase that inable him to see his whole face complete ly if (1)man is one eyed(2)man is two eyed

What are the smallest thicknesses of a soap bubble that produce constructive interference visible light of 380 nm (violet) and 760 nm (red).? And (b) the smallest thicknesses will give destructive interference? The index of refraction of soap is 1.33.

Red light of 650 nm travels from air to water with an incident angle of 30 degree.The refraction index for air is 1.000293 and for water is 1.33, the speed of light in vacuum is 3x10^8 m/s. a) Find the frequency, wave length, and speed of the red light in the air; b) find the frequency, wave length, and speed of light of the red light in water; c) find the angle of the refraction

Calculate the energy of a single photon of blue light with a wavelength of 4.63×102 nm.

A laser whose wavelength is λa = 4.7 × 10-7 m shines through a diffraction grating. The light hits a screen L
= 3 m away and fourth order maximum is detected 0.52 m on either side of the central maximum.
(a) What is the separation between the slits?
(b) What is the path difference from the diffraction grating to the fourth maximum, measured in meters?
(a) A new laser whose wavelength is λb = 6.3 × 10-7 m shines through the slits and both its fourth
maximums are labeled. What is the distance from the fourth order maximum using λa and the closest
fourth maximum using λb?

A ray of light is incident at an angle (α) on a planar end of a transparent cylindrical glass rod of refractive index (µ). Determine the least value of µ so that light entering the rod does not emerge from the curved surface of the rod irrespective of the angle α.