(a(i))[2]
State the meaning of threshold frequency.
(a(ii))[2]
Calculate the threshold frequency for platinum metal.
(b)[2]
A continuous spectrum of electromagnetic radiation with wavelengths from $300\,\text{nm}$ to $600\,\text{nm}$ is shone, one metal at a time, onto each of the metals listed in Fig. 7.1. Determine which of these metals, if any, will produce emission of electrons.
(c)[3]
When light of a particular intensity and frequency falls on a metal surface, electrons are emitted. State and explain the effect, if any, on the rate of electron emission from this surface when light of the same intensity but higher frequency is used.