Photons — Prelims Questions

A photon of wavelength $400,\text{nm}$ strikes a metal surface with a work function of $2.1,\text{eV}$. What is the maximum kinetic energy of the emitted photoelectrons? (Given: $h = 6.63 \times 10^{-34},\text{J}cdot\text{s}$, $c = 3 \times 10^8,\text{m/s}$, $1,\text{eV} = 1.6 \times 10^{-19},\text{J}$)

Which of the following properties is NOT characteristic of a photon?

If the wavelength of a photon is doubled, how does its momentum change?

A light source emits $10^{18}$ photons per second, each with an energy of $2,\text{eV}$. What is the power of the light source? (Given: $1,\text{eV} = 1.6 \times 10^{-19},\text{J}$)

Which of the following phenomena provides the strongest evidence for the particle nature of light (photons)?

A photon of energy $E$ has momentum $p$. If the energy of the photon is increased to $2E$, what will be its new momentum?