An LED is constructed from a pn junction based on a certain semi - conducting material whose energy gap is 1.9 eV .Then the wavelength of the emitted light is :

An LED is constructed from a pn junction based on a certain semi - con

1.	An LED is constructed from a pn junction based on a certain semi - conducting material whose energy gap is 1.9 eV .Then the wavelength of the emitted light is :
Answer» `1.6xx10^(8)m` `9.1xx10^(-5)m` `2.9 xx1^(-9)m` `6.5xx10^(-7)m` Solution :GIVEN `E=1.9 EV` `E=(hc)/LAMDA` , `IMPLIES lamda =(hc)/E=(6.62xx10^(-34)xx3xx10^6)/(1.9xx1.6xx10^(-19))` `lamda = 6.5 xx10^(-7)m`.

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An LED is constructed from a pn junction based on a certain semi - conducting material whose energy gap is 1.9 eV .Then the wavelength of the emitted light is :

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