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An LED is constructed from a p-n junctio...

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

A

1046nm and blue colour

B

654 nm and orange colour

C

654 nm and red colour

D

1046nm and red colour

Text Solution

Verified by Experts

The correct Answer is:
C
`lamda=(hc)/E=(6.6xx10^(-34)xx3xx10^8)/(1.9 xx1.6 xx10^(-19))=6.54 xx10^(-7)`
`=654 nm`
Red colour.
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