Investigating Thermometers and Temperature
Roberta Gibson
Although temperature is a part of our everyday lives and it may seem mundane, investigating how it is measured and how it varies is an important aspect of weather and weather forecasting. With a minimal amount of equipment, the possibilities for exploration and learning are literally endless. For example, studying temperature in the winter can be a good introduction to negative numbers.
To study temperature, you will need to obtain at least three good quality thermometers for your children. Be sure to explain how to use them accurately and what the numbers mean before you let them start.
You can start with an indoor project to look at room temperature and convection (air currents) within your house. Place one thermometer at the floor level, one at eye level, and one near the ceiling. Allow temperatures to stabilize (stop changing rapidly) and then take a few readings.
- Are all the temperatures the same? You might be surprised to find out how much they can vary.
- What happens if a fan is turned on nearby?
- Or if there is a heater or air conditioning vent nearby?
- If available, compare the second floor of a building with the first floor. We all know heat rises; did the readings support this?
- Why or why not?
To investigate conduction (the movement of heat through materials) and properties of insulation, try placing one thermometer outside on a sunny window, one inside on the same window, and one on the wall nearby on the inside.
- How do the readings compare?
- Is glass or is the wall a better conductor of heat?
On a hot summer day, the results may astound you. We purchased insulated curtains after doing this experiment.
To investigate insulation further, set out five styrofoam cups. Half fill one with water, one with moist soil, one with dry soil or sand, one with sugar, and leave one empty. Suspend a thermometer in each and record the temperature. Add an ice cube to each, covering it with the soil, sand, and sugar. Immediately record the temperature in each cup, taking care not to touch the ice cube with the thermometer.
- Which cup had the highest temperature and which had the lowest?
- Does the temperature change over time (for example, every ten minutes)?
- Is that what you thought would happen?
Are humans good at telling the temperature? Gather three cups or bowls (any size or shape will do as long as they hold roughly the same amount). Fill the first with cold water from the refrigerator, the second with medium temperature tap water and the third with warm water from the tap (not so hot as to burn). Have someone place their hand in the cold water for 30 seconds or so. Now present them with the medium water or warm water cup (unmarked) and have them guess which it is by testing the water temperature with the hand that had been in cold water. Now have them leave their hands in the warm water for 30 seconds or so. Present them with the medium or cold water cup and see how well they guess which it is.
Is the temperature reported in the news taken in the sun or shade and why? Place a thermometer on a flat surface in the sun. Place another in the shade nearby. Allow the temperature to stabilize and compare the two readings. Now repeat the experiment, but place the thermometers in cups of water. Once again, allow the temperatures stabilize (should only take a few minutes or so). How do the results change?
If you want to extend this activity, have the children record the temperature in a shady location every hour or every two hours over a period of days. Graph the results and see if any patterns emerge. Have them record any weather events, such as storms, that might have changed the temperature. Compare the results with local weather reports.
Try to get a tour of a television weather station or visit the weather sites on the Internet. See how weather patterns change for the entire country. If your children become really interested in the weather, have them build their own weather station out of household materials. The Eyewitness Books: Weather book and Franklin’s Forecast website both have information for doing this.
Of course, don’t forget just going outside and taking a look at the weather every day in all of its various forms. It’s one of the great wonders of our planet Earth.
Resources
Books
- Robert Gardener, and Eric Kemer, Science Projects About Temperature and Heat, Enslow Publishers, Inc., Berkeley Heights, NJ, 1994; ISBN: 0894905341.
- Judith Hann, How Science Works, Reader's Digest Association, Pleasantville, NY, 1991; ISBN: 0895773821.
- Brenda Walpole, Temperature (Measure up With Science), Gareth Stevens Publishing, Milwaukee, WI, 1995; ISBN: 0836813634.
- Jack Williams, USA Today, The Weather Book, 2nd Rev. ed., Vintage Books, 1997; ISBN: 0679776656.
Web Sites
Copyright August 2002
Originally published in July/August 2002 issue of HELM (Home Education Learning Magazine)
