Physics

Problem

Radiation of frequency

1.5\times10^{15}\,\text{Hz}

produces a stopping potential of

2.0\,\text{V}

when incident on a certain metal surface under vacuum. (Take

h = 6.63\times10^{-34}\,\text{J s}

and

e = 1.6\times10^{-19}\,\text{C}

.) a. (i) Calculate the work function of the metal in eV. b. (ii) Find the stopping potential when radiation of frequency

2.0\times10^{15}\,\text{Hz}

is used on the same surface under identical conditions.