PHYSICS · Multi-part · A Level · Physics · Particles and radiation · Particles and radiation
Problem
In a photoelectric experiment on an unknown metal, the following observations were recorded:
• For incident light of frequency 6.0×1014Hz, the stopping potential was 0.50V.
• For incident light of frequency 8.0×1014Hz, the stopping potential was 2.10V.
(i) Using the above data, calculate the numerical value of Planck’s constant.
(ii) Determine the threshold frequency of the metal.
(iii) Hence find the minimum energy, in electron-volt, required to liberate an electron from the metal surface.
(Take e=1.6×10−19C.)