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Compute power internally generated within a double-heterojunction LED if it has internal quantum efficiency of 64.5 % and drive current of 40 mA with a peak emission wavelength of 0.82 μm.

Compute power internally generated within a double-heterojunction LED if it has internal quantum efficiency of 64.5 % and drive current of 40 mA with a peak emission wavelength of 0.82 μm. Correct Answer 0.039

The power internally generated within device i.e. double-heterojunction LED can be computed by Pint = ηint hci/eλ = 0.645×6.626×10-34×3×108×40×10-3/ 1.602×10-19 × 0.82 × 10-6 = 0.039 W Where ηint = internal quantum efficiency h = Planck’s constant c = velocity of light i = drive current e = electron charge λ = wavelength.

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