Concepts Of Physics MCQ Edition [Volume 2]PhysicsPhotoelectric Effect and Wave–Particle Duality
Determine the maximum kinetic energy of the photoelectrons emitted when light of wavelength 350 nm strikes a cesium surface. The work function of cesium is 1.9 eV .
Options
- A3.5 eV
- B1.6 eV
- C2.4 eV
- D5.4 eV
Correct answer
B. 1.6 eV
Step-by-step solution
The energy of the incident photon is given by E = hc Using hc 1240 eV nm and = 350 nm : E = 1240 350 3.54 eV According to Einstein's photoelectric equation, the maximum kinetic energy of the emitted photoelectrons is: K_ max = E - Substituting the values of E and the work function = 1.9 eV : K_ max = 3.54 eV - 1.9 eV = 1.64 eV The closest value among the given options is 1.6 eV .