Work Function — MCQ Practice

The work function of a metal is $3.3,\text{eV}$. What is the threshold frequency for the photoelectric emission from this metal? (Given Planck's constant $h = 6.6 \times 10^{-34},\text{J s}$ and $1,\text{eV} = 1.6 \times 10^{-19},\text{J}$)

Light of wavelength $400,\text{nm}$ is incident on a metal plate. If the work function of the metal is $2.5,\text{eV}$, what is the maximum kinetic energy of the emitted photoelectrons? (Given $h = 6.626 \times 10^{-34},\text{J s}$, $c = 3 \times 10^8,\text{m/s}$, $1,\text{eV} = 1.602 \times 10^{-19},\text{J}$)

Which of the following statements about the work function ($\phi$) is INCORRECT?

A metal surface has a threshold wavelength of $600,\text{nm}$. What is its work function in electron volts? (Given $h = 6.626 \times 10^{-34},\text{J s}$, $c = 3 \times 10^8,\text{m/s}$, $1,\text{eV} = 1.602 \times 10^{-19},\text{J}$)

Two metals, A and B, have work functions of $2.0,\text{eV}$ and $4.0,\text{eV}$ respectively. If light of frequency $8.0 \times 10^{14},\text{Hz}$ is incident on both metals, which metal(s) will exhibit photoelectric emission? (Given $h = 6.6 \times 10^{-34},\text{J s}$, $1,\text{eV} = 1.6 \times 10^{-19},\text{J}$)

The work function of a metal is $4.14,\text{eV}$. What is the threshold wavelength for this metal? (Given $hc = 1240,\text{eV nm}$ for convenience)

If the work function of a metal is increased, what happens to its threshold frequency and threshold wavelength?