An electron has kinetic energy 2.8×10−23J. De-Broglie wavelength will be nearly
(me=9.1×10−31kg)
9.28 × 10-8 m
From De-Broglie wave equation, we get
λ = hp ⇒ λ = hmv
&K.E=12mv2⇒ v = √2KEm
Now,λ = hλ
&v=√2KEm
⇒ λ = h√2mKE
⇒ λ =6.62×10−24√2×9.1×10−31×2.8×10−23
⇒ λ=9.28 × 10−8m