Fill in appropriate word/words in the blanks given below. a) The correct relation for intensity of scattered light is I α __________ b) During dispersion, _____________light bends minimum and ____________bends maximum. c) Rainbow is a ________________formed naturally. d) The apparent position of a star is ________________because of atmospheric ________________ e) The three optical phenomenon which give rise to a rainbow are____________,_____________and____________ f) ________________light gets easily scattered because of ________________________ g) _______________________light is used in danger signals because_______________________________________ h) If the size of scattering particle is large enough ,then the scattered light may even appear __________ i)Write the correct relation in the given blanks. A+ ______ = i + ________ 1. What is meant by power of accommodation of the eye? 2. What do you mean by dispersion? 3. How do we see colours? 4.Why are danger signal lights red in colour? 5.On what factor does the intensity of scattered light depend?
Answers
Dispersion is a statistical term that describes the size of the distribution of values expected for a particular variable. Dispersion can be measured by several different statistics, such as range, variance, and standard deviation.
The ability of the eye lens to adjust its focal length, so as to clearly focus rays coming from distant as well a near object on the retina, is called the power of accommodation of the eye
As the red light has the highest wavelength among all the colours, so it is scattered the least. Due to which most of the light gets reflected back and can travel longer distances through rain, fog, dust etc. to reach our eyes effectively
The intensity of scattered light is found to be inversely proportional to the fourth power of wavelength of light. This relation holds when the size of air molecules is much smaller than the wavelength of the light incident
1 . Accommodation is the process by which the vertebrate eye changes optical power to maintain a clear image or focus on an object as its distance varies. ... Fish and amphibians vary the power by changing the distance between a rigid lens and the retina with muscles.
2 . Dispersion is a statistical term that describes the size of the distribution of values expected for a particular variable. Dispersion can be measured by several different statistics, such as range, variance, and standard deviation.
3 . The human eye and brain together translate light into color. Light receptors within the eye transmit messages to the brain, which produces the familiar sensations of color. Newton observed that color is not inherent in objects. Rather, the surface of an object reflects some colors and absorbs all the others.
4 . Why are the danger signals red in color? Ans. When the light passes through atmosphere, it gets scattered by small air particles. The scattering of light is inversely proportional to the fourth power of its wavelength.
5 . The intensity of scattered light is found to be inversely proportional to the fourth power of wavelength of light. This relation holds when the size of air molecules is much smaller than the wavelength of the light incident.