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Derivation of bohr's postulates of quantisation of angular momentum from de- broglie eq.

Derivation of bohr's postulates of quantisation  of angular momentum from de -broglie eq. 

proff...

 we know circumference of circular orbit must be integral multiple of wavelength .

   2πr= n×√  

 we also know that √ = h/ ( m×V) 

 putting value of √ in eq. we get

    2πr= (n×h) /(m×V) 

 or mVr= (n×h)/2π

which states that angular momentum should be integral multiple of h/2π

 in other words angular momentum is quantized. it can have certain fixed value.

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