Adaptations for Life in the Cold: Teacher Information

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Computer Information

This lab was designed to work on a Macintosh computer, but it can be modified to work on other computers. The computer equipment that is needed to make this lab work comes from Vernier. You need a serial box (SBI), Direct Connect Temperature Probe (DCT-DIN), and Data Logger Software (DL-SBI). These can be purchased from Vernier. The address is:

2920 S.W. 89th Street
Portland, OR 97225
phone: (503)-297-5317

Safety

CAUTION: Caution students about working around liquids and computers and electrical outlets.

CAUTION: Caution students about hot liquids. (The temperature should be around 37°C, which is body temperature and should not burn anyone.)

Laboratory

The cups can be the paper type used to hold hot liquids, or yogurt containers work well. The cups can be marked to hold 200 ml of water by marking them with a permanent marker.

The feather apparatus is made by using a feather pillow and knee-high stockings. Fill the stocking feathers prior to class.

The foam rubber cover can be made by purchasing a foam rubber egg carton mattress and cutting it to size to surround the cup.

Sand or soil can be purchased at any discount department store with a garden center or a garden shop. Note: if sand is used, the cup actually cools down faster than the control due to the heat capacity of sand and the fact there are very few pockets of air in the sand.

Software

The software that is used in conjunction with the temperature probe is Data Logger. It can be purchased for the Mac, IBM, or Apple. The following instructions are for the Macintosh but can be modified for either the IBM or Apple. This following details how to make the template for the laboratory exercise:

Load Data Logger on to the computers and open it up.
You will notice three icons: Data Logger 4.06, Default, Experiment Files.
One nice feature of Data Logger is that they have made some templates for their probes, and they can be modified to fit your own experiment and then saved under your own title for the students. The following steps work nice for this experiment:
It is important that you try this lab and these software setting out first so that you can modify them to meet the particular needs of your own experiment.
Be sure you have the experimental apparatus set up for this experiment by connecting the serial box to the computer through the modem port, the temperature probe is connected to Port 1 on the serial box.
Open up Experiment Files
Open up the file that says Direct-Connect Temp
When you do that a dialog box will appear and ask you if you want to the load the calibration saved with this experiment ("Direct-Connect Temp.CLB")? Click Yes. It will load the calibration file.
A graph will appear.
Pull down the Collect Menu and highlight Display Inputs. This allows you to see what the sensor is actually sensing at any given time at the bottom of the graph under the x axis by the word Temperature. You can enlarge this feature by pulling down the Windows menu and highlight on Big Numbers.
Pull down the Collect Menu and click on All Graphs Live. This allows you to see the graph being made as data is being collected.
Pull down the Collect Menu and click on Data Rate, a dialog box should appear, you will notice that it should be set at 2 pts. per second change this to 5 pt per minute and click OK or press the return key on the key board.
The axes of the graph is modified by first highlighting the last number on the X axis, Time (minutes). Now type in the amount of time you wish to run the experiment for. Type in 10. This means that the experiment will run for 10 minutes. The Y axis should have a range of 30-45.
If it does not have this range, then highlight the top number, and type in 45 and highlight the lower number and type in 35. The temperature of the water only cools down .5° to 2° C.
Put the probe into water along with the thermometer. They should both have the same reading. If the probe does not, it should be calibrated. need to calibrate your machines. To calibrate the computer do the following:
Take a beaker of water add ice to it to cool down the water. Put a thermometer in the ice water to get a temperature reading. Have second beaker of very warm or hot water ready.
Pull down Collect Menu and highlight Calibrate Deg C...
A dialog box will appear and say, How would you like to calibrate the probes? Click on Calibrate Now or press the return key on the key board.
A dialog box will appear and say, Which ports would you like to calibrate? Click on Port 1 only as this is where the temperature probe is located.
A dialog box will appear and say, Wait for the reading to stabilize. Now place the probe and a thermometer in the ice water and wait for the voltage to stabilize and once it has click on Stable or press return on the key board.
A dialog box will appear , and now type in the temperature reading that registers on the thermometer. Once you type in this reading, click OK or press return on the key board.
A dialog box will appear and say to Place the Temperature probe in a different known situation... at this time place the temperature probe and the thermometer into the warm beaker of water and wait for the reading to stabilize. Once it is stabilized click Stable or press the return key on the key board.
A dialog box will appear now type in the temperature reading that registers on the thermometer. Once you type in this reading, click OK or press return on the key board.
Another dialog box will appear with the specifications of the calibrations, if they are acceptable to you, press the return key or click on OK.
Once you have accomplished this, you can save your experiment so that you do not have to set the software again. Pull down the File Menu and highlight Save Experiment As ... A dialog box will appear type in the name you would like to name your lab. Decide where you want to save this on the hard drive or a disc. Highlight Save. Another dialog box will appear and ask you if you would like to save the calibration for this experiment. Click Yes. Now the experiment can be used by your students without having to set up the software. As long as you use that same probe with the same computer, the calibration should be good for some time to come.

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