A metal surface has a threshold wavelength of

PHYSICS · Multi-part · A Level · Physics · Particles and radiation · Particles and radiation

Problem

A metal surface has a threshold wavelength of 620 nm620\,\text{nm}. It is exposed to light of wavelength 400 nm400\,\text{nm}. (i) Calculate the work function of the metal in electron-volt. (ii) Find the maximum kinetic energy of the emitted electrons in joule and in electron-volt. (iii) Compute the stopping potential required to block these photo-electrons. (Use h=6.63×10−34 J sh = 6.63\times10^{-34}\,\text{J s}, c=3.00×108 m s−1c = 3.00\times10^{8}\,\text{m s}^{-1}, e=1.6×10−19 Ce = 1.6\times10^{-19}\,\text{C}.)

Related theory

Browse the problem library