A metal surface with work function Φ \Phi\,Φ is illuminated by a monochromatic light source of wavelength λ \lambda\,λ and power PPP. Under these conditions, the energy of each incident photon is 3Φ3\Phi3Φ, and photoelectrons are emitted.
The light source is then replaced by another monochromatic source of wavelength 2λ 2\lambda\,2λ and power 2P2P2P.
Assuming the quantum efficiency (the ratio of emitted photoelectrons to incident photons) remains constant, which of the following correctly describes how the maximum kinetic energy of the emitted photoelectrons and the rate of photoelectron emission change?
The maximum kinetic energy is halved, and the rate of photoelectron emission is doubled.
The maximum kinetic energy is quartered, and the rate of photoelectron emission is quadrupled.
The maximum kinetic energy is quartered, and the rate of photoelectron emission is doubled.
The maximum kinetic energy is halved, and the rate of photoelectron emission is quadrupled.
31 exam-style questions on AQA A Level Physics Electromagnetic radiation and quantum phenomena, covering The photoelectric effect, Collisions of electrons with atoms, Energy levels and photon emission, and Wave-particle duality. Each one has a worked solution and a mark scheme showing where the marks go.