The acceptor level of a p-type semiconductor is 6 eV. The maximum wavelength of light which can create a hole would be : Given hc=1242 eV nm.

Solution

Physics sir · 3 steps

Longest wavelength means the weakest photon that still works, so its energy must be exactly 6 eV.

1. Energy needed. A hole is created when a photon lifts an electron up to the acceptor level. The photon must carry at least 6 eV.
2. Why maximum wavelength. Photon energy is E = hc/λ, so a longer wavelength means less energy. The longest wavelength that still works is the one whose energy is exactly 6 eV.

   λₘₐₓ = hc/E = (1242 eV nm)/(6 eV) = 207 nm

3. So. The maximum wavelength is 207 nm, option (d).

The idea to keep. Threshold questions work the same way every time: the minimum energy gives the maximum wavelength. Use λ = 1242/E with E in eV to get λ in nm.

Answer from the NTA final answer key. Solution by PrepWiser.