### Notes:

The Photoelectric Effect is an adjustable-size file that displays nicely on smart phones, on tablets such as the iPad, on Chromebooks, and on laptops and desktops. The size of the Interactive can be scaled to fit the device that it is displayed on. The compatibility with smart phones, iPads, other tablets, and Chromebooks make it a perfect tool for use in a 1:1 classroom.

### Teaching Ideas and Suggestions:

The Photoelectric Effect simultation consists of two parts:
• an examination of the actual results that were eventually explained by a photon model of light
• a depiction of what would have been predicted based on the wave model of light
The simulation includes four input parameters - intensity of light, wavelength of light, the applied voltage to the circuit, and the identity of the metal that the light is incident upon. The animation depicts the stream of photons incident upon the metal. Color is added to the stream and changes as the wavelength is changed. The photons are depicted by dots; the density of the dots increases with increasing intensity. Electrons are emitted for energies exceeding the work function. The ejected electrons result in a clockwise flow of electrons through the circuit. The voltage can be modified to stop the current flow, resulting in the measurement of a stopping potential that is associated with the maximum kinetic energy of the ejected electron. There are two metals that can be studied - sodium and magnesium - and an unknown metal. Each has a different work function and would require different threshold wavelengths to eject an electron.

The Physics Classroom has prepared a student activity sheet for use with this simulation. Teachers are welcome to download and use it with their classes. Do you do NGSS? You'll find great alignment between our activity and HS-PS4-3.

Evaluate the claims, evidence, and reasoning  behind the idea that electromagnetic radiation can be described either by a wave model or a particle model, and that for some situations one model is more useful than the other.

View Student Activity Sheet

### Credits

The Physics Classroom would like to extend a special thanks to Nerd Island Studios for the creation of this HTML5 Interactive. Visit their website (http://www.nerdislandstudios.com) to see more great stuff by Nerd Island Studios.