MHT CET202122 Sep 2021Evening ShiftPhysicsDual Nature of MatterActual
Photons of energy 10 eV are incident on a photosensitive surface of threshold frequency 2 10¹⁵ ~Hz . The kinetic energy in eV of the photoelectrons emitted is [Planck's constant h =6.63 10³⁴ Js ]
Options
- A8.29 eV
- B6.5 eV
- C4.2 eV
- D1.7 eV
Correct answer
D. 1.7 eV
Step-by-step solution
aligned & Energy of photons, h v=10 eV & Threshold frequency =2 10¹⁵ ~Hz & Work function, W ₀= h v₀ & =6.63 10⁻³⁴ 2 10¹⁵ & =13.26 10⁻¹⁹ ~J & = 13.26 10⁻¹⁹ 1.6 10⁻¹⁹ eV =8.3 eV & KE of electrons = h v- W ₀ & =10-8.3=1.7 eV aligned