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Semiconductors

JEE Main level, single correct, medium

125 of 209

Question 125 of 209

LED is constructed from $Ga-As-P$ semiconducting material. The energy gap of this LED is $1.9eV$ . Calculate the wavelength of light emitted and its colour. $h=6.63\times {10}^{-34}J-s$ and $c=3\times {10}^{8}m{s}^{-1}$

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Answer: (A) $654nm$ and red colour

\lambda =\dfrac{hc}{E}=\dfrac{6.6\times {10}^{-34}\times 3\times {10}^{8}}{1.9\times 1.6\times {10}^{-19}}=6.54\times {10}^{-7}

=654nm

Red color

JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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JEE Main Physics practice question on Semiconductors (Special purpose diodes), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.