Question:

The wavelength λe of an electron and λp of a photon of same energy E are related by :

λp∝√λe

λp∝1/√λe

λp∝λ2e

λp∝λe

Wavelength of electron, λe=h√2mE
Wavelength of photon, λp=hc/E
λ2e=h2/2mE
λ2e=h2/2mhcλp
⇒λ2e∝λp