Page 1 :
p/?, , roblems For Practice, , bE, , J, , —, , 10., , 11,, , , , The speed of the yellow light in a certain liquid 1s, 2.4x108 ms. Find the refractive index of the, liquid. (Ans. 1.25), The wavelength range of the light that is visible to, an average human being is 400 nm to 700 nm. What, is the frequency range of this visible light ?, , (Ans. 4.3 x 10! Hz to 7.5 x 10'4 Hz), The wavelength of light coming from a sodium source, is 589 nm. What will be its wavelength in water ?, Refractive index of water is 1.33. (Ans. 443 nm), Light travels a certain distance in water in 3 ps., How much time it would take for light to travel the, same distance in air ? Refractive index of water, = 4/3. (Ans. 2.25 ps), , Red light of wavelength 750 nm enters a glass plate, of refractive index 1.5. If the velocity of light in, vacuum is 3x10°ms™, calculate in the glass, (i) frequency (ii) velocity and (iii) wavelength of, light. [Punjab 94C], [Ans. (i) 4x10" Hz (ii) 2x 10° ms~! (iii) 500 nm], The absolute.refractive indices of glass and water, are 3/2and 4/3. Determine the ratio of the speeds, of light in glass and water. (Ans. 8: 9), , The refractive index of glass with respect to water is, 1.125. If the speed of light in water is 2.25 x 10° ms!, then calculate the speed of light in glass., | (Ans. 2.0 x 10°ms™"), The refractive index of glass is 1.5 and that of water, is 1.3, the speed of light in water is 2.25 x 10°ms~"., What is the speed of light in glass ? [ISCE 96], (Ans. 1.95 x 10° ms‘), The ratio of the thickness of the strips of two, transparent media A and Bis 3: 2. If light takes the, same time in passing through both of them, then, what is the refractive index of Bwith respect to A?, , (Ans. 1.5), The speed of light in air is 3 x 10°ms_!. If refractive, index of glass is 1.5, find the time taken by light to, travel a distance of 10 cm in glass. (Ans. 9 x 107° s), , A light wave has a frequency of 5 x 10'* Hz. Find, the difference in its wavelengths in alcohol of, , refractive index 1.35 and glass of refractive index, 1.5. (Ans. 449 A)