Science

Assignment 11a: Heating and cooling analysis Name _____________________

(15 points), Due Monday 11/16 at 9 AM (needs to be before class you will lose ½ credit immediately)

(3 points for a reasonable graph, 2 points for each question)

Experiment. Two beakers, one filled with soil and one filled with water are heated and then allowed to cool.

Procedure: Turned heat lamp on. Measured the temperature every three minutes. At 12 minutes, turned heat lamp off. Continued measuring temperature every three minutes.

Data Table Temperature to Heat up

Time	Initial, t=0 min	3 minutes	6 minutes	9 minutes	12 minutes
Water Temp	23.3 oC	24.1 oC	24.5 oC	25.1 oC	25.6 oC
Soil Temp	24.9 oC	27.7 oC	29.3 oC	30.3 oC	31.2 oC

Data Table Temperature to Cool Down

Time (min)	15 minutes	18 minutes	21 minutes	24 minutes
Water Temp	25.5 oC	25.5 oC	25.5 oC	25.5 oC
Soil Temp	30.0 oC	29.2 oC	28.6 oC	28.1 oC

First, make a graph of temperature vs. time. You can use the graph paper provided, or make your own with a ruler and a piece of paper. Put both results on a single graph. Use a solid line for the water temperature and a dashed or dotted line for the soil temperature. Then answer the following 6 questions.

1. Based upon the data provided, which material heated up the fastest: water or land? Support your answer with evidence from the lab.

2. Which material cooled the fastest once the light was turned off? Support your answer with evidence from the lab.

Assignment 11a: Heating and cooling analysis, page 2 Name _____________________

3. How might these results compare to your expectations? In a conventional Lab, this would be your hypothesis before doing the experiment. (you might consider your experiences at, for example, the beach or at a pool where you compare differences in ground temperature vs. water temperature).

4. Air in the troposphere is heated from the bottom up by heat given off by the surface. This Lab shows that the type of surface can matter. How might this affect a city located near an ocean vs. a city that is inland and far from a body of water? Locate Seattle, Washington and Bismarck, North Dakota on Google Maps. If the sun shines equally on both Seattle and Bismarck, which location would get hotter during the day? Explain.

5. Based on the results of the lab, which city would probably have a bigger difference between its day and night temperatures?

6. Anchorage (southern coast of Alaska) is 15 degrees of latitude north of Minneapolis, so it receives very indirect rays in winter, yet its January temperatures are similar to Minneapolis’s. Explain why.