The de-Broglie wavelength of an electron having 80 eV energy is nearly (1 eV =1.6 10⁻¹⁹ ~J . , Mass of the electron =9 10^ -n ~kg , Planck's constant .=6.6 10⁻³⁴ ~J - s )

Step-by-step solution

Kinetic energy, KE =80 eV aligned & =80 1.6 10⁻¹⁹ ~J & =128 10⁻¹⁹ ~J aligned De-Broglie wavelength aligned = h 2 m( KE ) & = 6.6 10⁻³⁴ 2 9 10⁻³¹ 128 10⁻¹⁹ & = 6.6 10⁻³⁴ 256 9 10⁻⁵⁰ & = 6.6 10⁻³⁴ 16 3 10⁻²⁵ = 6.6 48 10⁻⁹ & = 66 48 10⁻¹⁰ & =1.4 10⁻¹⁰ ~m & =1.4 Ã… aligned