A beam of monochromatic light of frequency $f\,$ is incident on a metal surface with work function $Φ\Phi$ , where $\Phi$ . This causes photoelectrons to be emitted at a rate $R$ (number of photoelectrons emitted per second). The maximum kinetic energy of the emitted photoelectrons is $E_k$ .

The frequency of the incident light is increased to $1.5f\,$ while the total power of the beam is kept constant.

Assuming the quantum efficiency (the ratio of emitted photoelectrons to incident photons) remains constant, which of the following correctly describes the new maximum kinetic energy $E'_k\,$ and the new rate of photoelectron emission $R^{'}$ ?

$E'_k > 1.5E_k$ and $\frac{2}{3}R$

$E'_k = 1.5E_k$ and $\frac{2}{3}R$

$E'_k > 1.5E_k$ and $R^{'} = 1.5 R$

$E'_k = 1.5E_k$ and $R^{'} = 1.5 R$

The frequency of the incident light is increased to $1.5f\,$ while the total power of the beam is kept constant.

$E'_k > 1.5E_k$ and $\frac{2}{3}R$

$E'_k = 1.5E_k$ and $\frac{2}{3}R$

$E'_k > 1.5E_k$ and $R^{'} = 1.5 R$

$E'_k = 1.5E_k$ and $R^{'} = 1.5 R$

Electromagnetic radiation and quantum phenomena

Question 20

Markscheme

Electromagnetic radiation and quantum phenomena

Question 20

Markscheme

Electromagnetic radiation and quantum phenomena

Question 20

Electromagnetic radiation and quantum phenomena Questions

Electromagnetic radiation and quantum phenomena

Question 20

Electromagnetic radiation and quantum phenomena Questions