When a ray of light enters a glass slab from air, its speed and wavelength , frequency………..

1 )  When a ray of light enters a glass slab from air , its speed and wavelength , frequency ………..

Its speed and wavelength ……….. ( Decreases ) , 

but frequency ………….. ( Remains constant ) .

because glass is denser medium and as we know that velocity of light in glass is lower than air . so by that reason velocity decreases . And velocity depends on refractive index of medium . Refractive index of medium is inversely proportional to speed of light . Refractive index of glass is greater than air . So speed of light decreases while entering to glass slab from air medium . And speed of light will increase while entering to air medium from glass slab .

We know a formula { v = f λ } , as  “ λ “ is wavelength , which is directly related to velocity by this formula . So when velocity increases , then wavelength also increases and vice versa . So here according to question , wavelength will get decrease .

If we talk about frequency , frequency works as a constant and frequency is also inherent property of a wave . So frequency will remain sameevery where either light enters denser medium or rare medium .

2 )   For production of beats, two waves must have ------------------- ,

A ) Same frequency ,                                  B ) Same wavelength ,

C ) Same velocity ,                                     D ) None of these ,

Correct Answer : -  A ) Same frequency ,

Beats are produced due to superposition of two waves which have slightly different frequencies and have identical amplitudes.

3 )  Beats is an application of --------------------- ,

A ) Superposition ,                                     B ) Interference ,

C ) Both of these ,                                       D ) None of these ,

Correct Answer : - A ) Superposition ,

Beats are produced due to propagation of superposition   ,  not by interference . And it must have even slightly different frequency .

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When a ray of light enters a glass slab from air ,

What happens when a ray of light enters a glass slab from air ,

Why do light rays band when pass through a glass slab ,

its speed and wavelength , frequency of a wave are related ,

For production of beats, two waves must have

Produce of beats two waves must have , Produce of beats two waves must having different ,

Beats is an application of , superposition theorem ,