Question -
Answer -
Wavelength of light of a sodium line, λ =589 nm = 589 × 10−9 m
Mass of an electron, me= 9.1 ×10−31 kg
Mass of a neutron, mn= 1.66 × 10−27 kg
Planck’s constant, h = 6.6× 10−34 Js
(a) For the kinetic energy K, ofan electron accelerating with a velocity v, we have the relation:We have the relation forde Broglie wavelength as:
Substituting equation (2)in equation (1), we get the relation:
Hence, the kinetic energy of the electron is6.9 × 10−25 J or 4.31 μeV.
(b) Using equation (3), we canwrite the relation for the kinetic energy of the neutron as:
Hence, the kinetic energy of the electron is6.9 × 10−25 J or 4.31 μeV.
Hence,the kinetic energy of the neutron is 3.78 × 10−28 J or 2.36neV.