The mean free path of electrons in a metal is 4 x 10⁻⁸ m. The electric field which can give on an average 2 eV energy to an electron in the metal will be in units of V/m

Options

(a) 5 x 10⁻¹¹
(b) 8 x 10⁻¹¹
(c) 5 x 10⁷
(d) 8 x 10⁷

Correct Answer:

5 x 10⁷

Explanation:

E = V / d = 2 / 4 x 10⁻⁸
0.5 x 10⁸ = 5 x 10⁷ Vm⁻¹