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2T diagram, HUMAN EYE, , It is, , :, , 3-Htt g, , Idiot, , Number !, , paired light, , a, , which helps, object around, , sensing, organ, see, us to, us, , #, , ,, , [, , ., , has lens in its structure, , It, , ., , PARTS OF HUMAN EYE, #, , CORNEA, , spherical membrane covering the, transparent enters, this, our eye, front of eye Light first, through, membrane, only, Dark muscular, between cornea and lens which, diaphragm, controls the size, , : It is, , a, , thin, , ,, , ., , ., , # IRIS, , :, , It, , #, , CRYSTALLINE :, LENS, , # PUPIL, , :, , Eye lens, , called, , Also, , jelly, , a, , pupil, , of, , ., , is the colour of Lois that, made of, , ,, , It is, , !7n"fdYijht light, :, , light, , dim, , muscles, , # RETINA, , as, , the colour of, , eye, , ,, , ., , is, , a convene, , lens, , ., , through which light enters the, the, lightdueentering, eye, to expansion of Iris, completely, , it opens up, , ,, , ., , soft and flexible material like, , A small hole between the iris, eye It regulates the amount of, , In, , :, , a, , call, , proteins Basically , it, , ., , # CILIARY, MUSCLES, , we, , :, , it becomes very small due to contraction of Iris, , ., , hold the lens in, joeyNature, of the lens, , position, , and, , help in modifying, , the, , ., , is, , delicate membrane which consists of, , light-sensitive, cells, It, , a, , numerous, , ., , ↳, ↳, , These, , sensitive cells, , light, , electric, generate, signal, Retina has 2, , type, , ', , 0,31¥, , #, , typo,, , ND, , :, , :, , It transits visual, The, , ., , of light sensitive cell, respond to intensity of light, , too, Rcoodnsg, primary, respond, These cells, These cells, , #, , get activated upon illumination, , point, , at, , to, , colours, , ., , information from retina to brain, , which the optic, , nerve, , leaves the eye, , ., , ., , and
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# AQUEOUS, , :, , HUMOUR, , and eye lens, their is a, space filled with transparent, liquid called the aqueous humour which helps the refracted light to be, focussed on retina It also provides nutrition to eye, , Between the, , cornea, , ., , ., , # VITREOUS, , between eye lens and retina is filled with, , space, , :, , a, , vitreous humour, , HUMOUR, , liquid, , called, , ., , Po wer of Accommodation, ,, , ↳, , ability of, , It is the, 3-HIT, , eye lens to adjust its focal length, tis object GT Idf Etf 3¥ clear That tf tht (or 344T focus that tf, , HH ) focal, , -, , ., , 2A 46¥ IHA l, , length, , ÷¥, , <, , similarly, 27, , CASE, , HI, , I:, , To see, , Focal, , Muscles, , Near, seen, , muscles, , lens, , =, , I, , most, , Increase, , ), Knick, lens, , q, , distance to which eye, , a, , can see, , ., , minimum distance at which an object can be, without any strain is called the least distance of, normal eye of an adult , it is 25cm, , the eye, , ., , (contracted), , Contract, Thick, , far point of eye, , distinctly, , (Relaxed), , fraysrefyoocnuasdontoy, , Decrease, length, point of the eye : maximum, is called, , clearly, point of, , ), , Thin, , nearby :, , distinct vision For, °, , "s), , Relaxed, , ,, , °, , object, , y, , =, , focal, far, , =, , =, , length, , To see, , Eye, , o, , 't, , lensthin, , far off :, , lens, , ciliary, K' B, , length, , FIT focal, length toy eft ,, tht tf ciliary muscle help that ed, , Eye, , :, , focal, , 4TH, , ciliary, CASE I, , f, •, •, , :, , ,, , ., , Cataract : Sometimes the crystalline lens of people at old, becomes, age, Milky and cloudy This condition is called cataract, ., , ., , °, , The, , minimum time for which, , we, , should view, , an, , object , so that, , its clear
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image, , formed, , is, , retina is, , on, , 4th, , of, , second, , a, , ., , have two eyes for vision and not just one ?, A human, has a horizontal field of view of about 1500 with one eye and, being, about 180 with two eyes So , two eyes give a wider field of view, , Why, , °, , we, , ., , ., , PRISM, ↳, , A, , fcbse, , least two lateral, other at certain, , ., , PQ Incident, Ef → Reflected, →, , LA, , →, →, , medium bounded, , transparent refracting, , at, byeach, , Rs, , 2017,2012), , Lik, , Ray, , Ray, Emergent Ray, Angle of Prism, , # DISPERSION, , OF, , Lo, , Le =, LD, , of, , angle, , seven, , =, , angle of emergence, , (LD, , angle of deviation, , Lit Le, , -, , LA, , ), , splitting, is called, , prism, , colours, , so, , A, , Dispersion, , ., , obtained, , spectrum, , ,, , ,, , speed, , the, , VIBGYOR (Violet ,, , Indigo, , ,, , Blue , Green, , ., , Why Dispersion occurs ?, of different colours travel, light, rays, in vacuum and air but in, the, same, , =, , GLASS PRISM : I close 20171, of white light into its constituent colours, when, , LIGHT BY, , Red ) is called, , Yellow , Orange ,, , ., , angle of incidence, angle of refraction, , WHITE, , The phenomenon of, it passes through a, This band, , =, , surfaces , inclined to, , with, , medium, they travel with different, speeds toand bend through different angles , which, leads, dispersion of light, **, a [ Cbse 202012017,20161, # Recombination of white light or, , any, , other, , ., , Reverse, , of, , dispersion, , is, , also possible, , ., , of the spectrum, lights, to, back white, , Seven coloured, can be recombined, , by pulsing, , two, , give, prisms , one upside, , # RAINBOW : A natural, the dispersion of, -, , atmosphere, , °, , °, , litght, , light, , down, , ., , spectrum produced, , sunlight by raindrops, , in the, , by, , ., , droplets acts as small prisms, droplets refract and disperse the incident, reflect internally and finally , reflect, sunlight then, it again when it comes out of raindrop, Water, Water, , ., , ,, , ., , of seven colours, , ,
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ATMOSPHERIC REFRACTION, when refraction takes place between two mediums and if one of the medium, is earth 's atmosphere then the process is called, atmospheric refraction, ., , Atmospheric Refraction :, , Effects of, *, , of, Twinkling, refraction of, , Ccb se 2018,2016), , is, , twinkling, the star, , StarlightConti nous, ,, , undergoes refraction, , the, star, , light, , star, , appears, , when viewed, , near, , the, , due to, , on, , entering, , atmospheric, , ., , night, , continuously, , ., , zoss], , plebs e, , As the, , light from, Atmosphere Tt undergoes refraction, to the, normal, , than, higher, they Actually, enters the Earth 's, , atmospheric isrefraction, of the star, slightly, to be, The star, , is, , the earth 's atmosphere, before it reaches the earth In this way ,, and the, increases and decreases, , appears, , and bends towards the, , #, , ly, , our, Starlight reaching, eyes, to be twinkle at, , # Star seem, a, , of stars, , stars : The, , are :, g, , each time due, , Therefore , the apparent position, different from its actual position, , ., , ., , higher, slightly, horizon, , than its actual, , position,, , ., , Planets do not Twinkle : The planets are much closer to the earth and are, considered a collection of a large number of point sized sources of light , the, total amount of light entering our eye from all the individual point sized, sources will, average out to zero , there by nullifying the twinkling effect, ., , Delayed, , # Advance Sunrise and, , Sunset : Klose 2016,20141, , visible to us two minutes before the, actual sunrise and about two minutes after, , The sun is, the, , actual sunset This is due to, ., , refraction, , Scattering, , The, , of, °, , of, , reflection of, , light, , atmospheric, , ., , light, , light, It depends, , labs e 20151, from, , object, , an, , in all directions is called scattering, ( III particle FF ctdna scatter STD, , type of particle, Very fine particles scatter mainly in blue colour, Large sized particle scatter light of longer wavelength, Shorter the wavelength, greater will be the scattering, ., , on, , ., , °, , ., , °, , ,, , Effects of scattering of, # Tyndall, , Effect, , heterogeneous, , : The, , light, , :, , earth's, , is a, atmosphere, smoke, , mixture of minute particles of, , ,, , ., , Tynedfffet
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scattering light, , dust of air which becomes visible due to, of, → Ccbse 2015g 20123, # Colour of sky is Blue : The molecules of air and other fine particles in the, atmosphere have smaller size and are more effective in scattering light of shooter, at the blue end than light of longer wavelengths at the end Thus,, when sunlight passes through the atmosphere , the fine particles in air scatter, the blue colour more strongly than red The scattered blue, enters our eyes, blue, which makes the colour of, , tiny water droplets ,, , wavelength, , ., , light, , ., , sky, , RB, , ., , ', , ., , If earth had no atmosphere than there would not have been any scattering, ,, then the, would have looked dark The, to, dark, sky appears, passengers, at, altitudes, flying very high • • in colour, red is least scattered, are, •, , as, fog or smoke,, Danger, by, light, therefore it can be seen in the same colour at a distance, 0, , sky, , ., , ., , 0, , signal, , ., , # Colour of Sun at sunrise and Sunset, , :, , Kb se 20131, , from the sun near the horizon passes through, Light, thicker, of air and larger distances in the, layers, earth 's, atmosphere before reaching our eyes, Near the horizon, most of the blue light and, ., , shorter, , wavelength, , are, , scattered, , particles Therefore , the light, eyes Ps of longer wavelengths, , the, reaches our, This give rise to the, , away by, that, , ., , ., , reddish appearance of, , sun, , .
