Ray Optics and Optical Instruments

Related Questions

• Angle of prism is A and its one surface is silvered. Light rays falling at an angle of incidence 2A on first surface return back through the same path after suffering reflection at second silvered surface. Refractive index of the material of prism is

  ---

• A lens of refractive index $n$ is put in a liquid of refractive index $n'$ of focal length of lens in air is $f$, its focal length in liquid will be

  ---

• An astronomical telescope has objective and eye-piece lens of powers 0.5 D and 20 D respectively, its magnifying power will be

  ---

• When light wave suffers reflection at the interface from air to glass, the change in phase of the reflected wave is equal to

  ---

• When a plane mirror is placed horizontally on a level ground at a distance of $60$ m from the foot of a tower, the top of the tower and its image in the mirror subtend an angle of $90^\circ $ at the eye. The height of the tower will be

  ---