A glass slab of thickness 2.5 cm having refractive index `5//3` is kept on an ink spot. A transparent beaker of very thin bottom containing water of R.1. `4//3` upto 8 cm is kept on the glass block.
Calculate the apparent depth of the ink spot, when seen from outside air.

A ray of light is incident normally on a glass slab of thickness 5 cm and refractive index 1.6. The time taken to travel by a ray from source to surface of slab is same as to travel through glass slab. The distance of source from the surface is

A glass slab of thickness 8 cm contains the same number of waves as 10 cm of water, when the same monochromatic light transverses both. If the refractive index of water is 4/3, then the refractive index of glass is

A glass slab of thickness 4 cm contains the same number of waves as X cm of water column when both are transverse by the same monochromatic light, If the refractive indices of glass and water ( for that light ) are 5/3 and 4/3 respectively, the value of X will be

Two point charges A and B of value +3muC and +2muC are kept 25cm apart in air. Calculate the work done when charge B is moved by 5cm towards A

If the refractive indices of glass and water with respect to air is 3/2 and 4/3 respectively. Calculate the velocity of light in glass and water.From these results calculate the refractive index of glass with respect to water. Given velocity of light in air is 3 xx 10^8m//s .

A layer of oil 3 cm thick is flowing on a layer of coloured wtater 5 cm thick. Refractive index of coloured water is (5)/(3) and the apparent depth of the two liquids appears to be (36)/(7) cm . What is the refractive index of oil?

A tank is filled with water to height of 12.5 cm. The apparent depth of a needl lying at the bottom of the tank is measured by a microscope to be 9.4 cm. What is the refractive index of water? If water is replaced by a liquid of refractive index 1.63 upto the same height, by what distance would the microscope have to be moved to focus on the needle again?

Convex lens is made of glass of refractive index 1.5 If the radius of curvature of each of the two surfaces is 20 cm find the ratio of the powers of the lens, when placed in air to its power, when immersed in a liquid of refractive index 1.25 .

An air bubble in a glass slab with refractive index 1.5 (near normal incidence ) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face, the thickness (in cm) of the slab is