PUMPA - SMART LEARNING

எங்கள் ஆசிரியர்களுடன் 1-ஆன்-1 ஆலோசனை நேரத்தைப் பெறுங்கள். டாப்பர் ஆவதற்கு நாங்கள் பயிற்சி அளிப்போம்

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Refraction of light rays from a plane transparent surface:
 
We have laws of refraction, just like laws of reflection. The following properties will be used to learn the laws of refraction.
a) When a ray of light travels from an optically rarer medium to an optically denser medium, it bends towards the normal.
 
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Rarer to denser medium
 
b) When a ray of light travels from an optically denser medium to an optically rarer medium, it bends away from the normal.
 
43 (1).png
Denser medium to rarer medium
 
c) A ray of light incident normally on a denser medium goes without any deviation.
 
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Light incident normally
  
The laws of refraction of light:
Laws of refraction, also known as Snell’s law of refraction, are given below as:
  • The incident ray, the refracted ray and the normal to the interface of two transparent media at the point of incidence all lie in the same plane. 
  • The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant for a light of given colour and  the given pair of media. If \(i\) is the angle of incidence and \(r\) is the angle of refraction, then.
SiniSinr=Constant

This constant is called the refractive index of the second medium with respect to the first medium. It is generally represented by the Greek letter \(µ\)(\(mew\)).
 
Note: The refractive index is the ratio of two similar quantities, so it has no unit. The speed of light in different media is also used to define a medium's refractive index.
 
μ=Speedoflightinvacuumorair(c)Speedoflightinthemedium(v)
 
In general,
 
μ21=Speedoflightinmedium1Speedoflightinmedium2