Escaping the sun LAB/class data (25 pts)

Go to CLEA and get the lab from here

Login and turn the layers ON for at least one trial for each Part.

Part A: Run the flow situation for a photon. Record the data in terms of # of layers vs. interactions. Collect data for 5, 10, 15, 20, and 25 layers

As the number of layers increases, what happens to the number of interactions? Is this a linear relationship, or an exponential relationship? How do you know?

Part B: Run the flow situation for a diffusion, and record the data as you did in Part A.

How did the data change when we had larger numbers of photons? Is this data more accurate or less accurate than that collected in Part A? Why do you think so?

Part C: Run the EXPERIMENT. The red cylinder represents the atmosphere, the line drawing at the right represents your eye, and the light at the left represents a photon leaving the light source.

Collect data for photons at 1.5 eV, 1.8 eV, 2.0 eV, 2.3 eV and 2.5 eV. Notice as you adjust the energy, you also adjust the wavelength.

Create a table as follows:

Energy (ev) Wavelength (nm) Photons sent Photons detected



As the energy of a photon increases, what happens to its wavelength? As the energy of a photon increases, what pattern is present for the number of photons detected? Why?


Part D: Run the EXPERIMENT again, but this time, set the photon energy level at 2.2 eV, and change the gas the element is traveling through.

This time, your table should look like this:

Energy (eV) Wavelength (nm) Gas Atoms Photons Sent Photons Detected

What effect do the different types of gas atoms have on the # of photons detected? What would this have to do with a line spectra? If you changed the energy of the photons and ran the experiment again and again, do you think you would continually get the same patterns? Why or why not?


This lab/class activity is due as a post on your blog on 9/24/2008.