Question -
Answer -
Kinetic energy of the electron, Ek =120 eV
Planck’s constant, h = 6.6× 10−34 Js
Mass of an electron, m =9.1 × 10−31 kg
Charge on an electron, e =1.6 × 10−19 C
(a) For the electron, wecan write the relation for kinetic energy as:
Where,
v = Speed of the electron
Momentum of the electron, p = mv
= 9.1 × 10−31 × 6.496 × 106
= 5.91 × 10−24 kg m s−1
Therefore, the momentum of the electron is5.91 × 10−24 kg m s−1.
(b) Speed of theelectron, v = 6.496 × 106 m/s
(c) De Brogliewavelength of an electron having a momentum p, is given as:
Therefore,the de Broglie wavelength of the electron is 0.112 nm.