Programacion

Photoelectric Effect


Name: ALVARO JAVIER TORRES REYES
http://phet.colorado.edu/sims/photoelectric/photoelectric.jnlp


1. Threshold Frequency and Work Function
a. Define:i. Threshold Frequency –



ii. Work Function –




b. Explore: Under Graphs, place a check next to Electron Energy vs. Light Frequency. Use this graph todetermine the threshold frequency and work function for each sample.

|Sample |Threshold Frequency |Work Function |
| |( x 1015Hz) |(eV) |
|Sodium | | |
|Zinc || |
|Copper | | |
|Platinum | ||
|Calcium | | |
|????? | ||


c. Using any one of the samples, determine the slope of the graph. Show your work below. Compare the magnitude of the slope to Planck’s constant.







2. What role doeslight intensity play in the Photoelectric Effect?


a. Key Concepts:
i. What is another word for the “intensity” of light?




ii. Electric current (coveredlater in our course) refers to the rate at which electrons flow. In this case, the current is increased by causing more electrons to flow.

b. Explore: Choose any one of the samples to usefor this experiment. Under graphs, make sure that both Electron Energy vs. Light Frequency and Current vs. Light Intensity are checked.


i. Below the Threshold Frequency –...