Activity 8: Exploration of Chemistry

1. Choose any Teaching Idea from any of the Chemistry Simulations (http://phet.colorado.edu/en/simulations/category/chemistry ) and post your results/data and/or answers on your blog.

Investigating the Green House Effect                                 Traci Radil

Colorado Standard: 2

Purpose:  Investigate how atmospheric changes affect global temperature

                Examine how clouds contribute to the greenhouse effect.

                Predict how changing greenhouse gas levels affect global temperature.

This lesson was designed to be used in a Global Science class. Students should have been introduced to the concept of the greenhouse effect and should have some idea of how it works. An example of a student handout follows.

Investigating the Green House Effect

You are a citizen concerned about the greenhouse effect and decide to do some research about the issue. You come across a great website that has a simulation on just this topic. Once you have run some simulations and made some observations you become more than concerned, you are downright outraged! The next step is to write a letter to the editor detailing your concern and using what you have learned as evidence in support of your position.

1. Go to http://phet.colorado.edu/en/simulation/greenhouse

2. Open up The Greenhouse Effect and explore all of its features.

3. Write down your observations of what happens during the three featured time periods: Today, 1750 and Ice Age.

Today: The Temp stays around 60ºF. There is a 70% rel. humidity.
             CO2: 388 ppm
             CH4: 1.843 ppm
             N2O: 0.317 ppm
1750:    The Temp stays around 57ºF. There is a 70% rel. humidity.
              CO2: 280 ppm
              CH4: 0.730 ppm

              N2O: 0.270 ppm
Ice Age: The Temp stays around 33ºF.
               CO2: 180 ppm
               CH4: 0.380 ppm

               N2O: 0.215 ppm

4. Change the number of clouds for each time period and write down your observations.

Overall the cloud cover blocked some sunlight photons from making their way to the surface. This in turn had a cooling affect on the overall temperature.  The number of clouds I chose was three.

Today:  The temps stays around 54ºF

1750:  The temps stays around 50ºF

Ice Age: The temps stays around 22ºF

5. Scientists predict CO₂ levels to increase to 490 – 1260 ppm by the end of the century. Run a simulation that will help you predict how this change will affect temperature. What do you find?

I think we will find that the average temperature is higher than it is today.  The average temperature that came in was 67ºF. 

2. Work with any of the Chemistry Simulations to create your own Teaching Idea. The criteria for this is as follows:
a. must identify and meet three (3) science education standards
b. must be original work
c. must be scientifically accurate and appropriate for the directed grade level.

Wave Lab

Wave on a String Simulation

Wave motion transfers energy from one point to another, often with no permanent displacement of the particles of the medium—that is, with little or no associated mass transport. They consist, instead, of oscillations or vibrations around almost fixed locations.

Amplitude is the magnitude of change in the oscillating variable with each oscillation within an oscillating system.

Frequency is the number of occurrences of a repeating event per unit time.

Damping is an effect that reduces the amplitude of oscillations in an oscillatory system


The experiment we will do is adjusting the amplitude of the wave. 

1. Select Oscillate.
2. Select the rulers so you can measure the height of the green circles.  If you pause the motion you can click the step button to move the wave in steps to measure the height of each green circle.
3. We will be using the fixed end for this scenario and the tension left on high.
Record your results in the chart below. This will be the max distance from the the center dotted line. 

4. Now repeat the same above but instead of fixed end set it to no end.

5. Given the above results what conclusion can we come to regarding changing the amplitude in regards to a loose and fixed end?  Did this change the results?

6.  If we keep the Amplitude and Frequency at 50 with the tension high what change takes place when we go higher or lower with Damping? What differences are there between fixed end and no end visually between the two? Compare the Damping set to 0 to the damping at 100. What difference do you see between these two?