The following logic gate is equivalent to :

Draw the output signal Y in the given combination of gates.

LED is constructed from Ga-As-P semiconducting material. The energy gap of this LED is 1.9 eV. Calculate the wavelength of light emitted and its colour.

[h = 6.63 $$\times$$ 10^$$-$$34 Js and c = 3 $$\times$$ 10⁸ ms^$$-$$1]

For extrinsic semiconductors; when doping level is increased;