Ray Optics and Optical Instruments

Related Questions

• The focal length of the objective and eye piece of a telescope are respectively 60 cm and 10 cm. The magnitude of the magnifying power when the image is formed at infinity is

  ---

• An achromatic combination of lenses produces

  ---

• A convex lens of focal length 84 cm is in contact with a concave lens of focal length 12 cm. The power of combination (in diopters) is

  ---

• In the figure, an air lens of radii of curvature 10 cm (${{R}_{1}}$ = ${{R}_{2}}$ = 10 cm) is cut in a cylinder of glass$(\mu =1.5)$. The focal length and the nature of the lens is

  ---

• A thin equiconvex lens is made of glass of refractive index 1.5 and its focal length is 0.2 m, if it acts as a concave lens of 0.5 m focal length when dipped in a liquid, the refractive index of the liquid is

  ---