# Waves behave like particles

##### Intros
###### Lessons
1. Waves Behave Like Particles
2. Introduction to particle model of waves.
3. New theory of quantum mechanics.
4. Wave practice duality of light
5. Compton effect
6. Compton experiment
##### Examples
###### Lessons
1. The stopping potential, $V_{0}$, that prevents electors from flowing across a certain photocell is 6.0V. What is the kinetic energy given to the electrons by incident light? Give your answer in both $J$ and $eV$. Sketch the problem and calculate your answer.
1. Potassium threshold wavelength is 564 nm,
1. Find the work function of potassium in $eV$.
2. If the ultraviolet radiation with a wavelength of 246 nm falls on potassium, what is the energy of the ejected electrons in $eV$. Sketch the problem and calculate your answer.
1. The stopping potential required to prevent current through a photocell is 4.2$V$. Calculate the kinetic energy in joules and in $eV$ of the photoelectrons as they are emitted.
1. The threshold wavelength of copper is 264 $nm$.
1. Find the threshold frequency of copper.
2. What is the work function in $eV$ of copper?
3. Copper in a photocell is irritated by ultraviolet light of 140 $nm$ wavelength. What is the kinetic energy of the photoelectrons in $eV$?
1. The work function for cadmium is 4.07 $eV$.
1. Find the threshold wavelength for cadmium.
2. What is the kinetic energy in $eV$ of photoelectrons ejected when 190 nm violet light falls on the cadmium?
1. An X ray with a wavelength 6.0 x 10-14 $m$ is travelling in a vacuum.
1. Calculate the momentum associated with this X ray.
2. Why does the X ray exhibit little particle behavior?
1. The work function of sodium is 2.28 $eV$.
1. What is the threshold wavelength of sodium?
2. Sodium is exposed to radiation of wavelength 160$nm$. What is the maximum kinetic energy of the ejected electrons in $eV$?