(a) For what K.E. of a neutron, will the associated de Broglie wavelength be `1.40xx 10^(-10)m`?
(b) Also find the de - Broglie wavelength of a neutron, in thermal equilibrium with matter, having an average kinetic energy of` (3//2)` kT at 300K

Explanation

(a) `6.686xx10^(-21)J=4.174xx10^(-2)eV`
(b) 0.145 nm