Unit 2: Exploring the Nature of Thermal Phenomena
Young children learn to stay away from hot stoves, to get mittens when going outside to play in the snow, and to sip carefully before drinking from a cup of hot cocoa when they come back inside. Such experiences can serve as resources on which to build when studying about thermal phenomena.
A. Connecting to what one already knows about thermal phenomena
One way to begin learning about a topic is to consider relevant everyday experiences and the language used to describe them:
Question 2.1 What are some everyday experiences you have had with thermal phenomena?
- How do you keep things hot or cold for a picnic?
- Adjust the temperature of water for a bath?
- Cook dinner?
Like many English words, the adjective thermal derives from a Greek root, in this case: thérme, which refers to heat.
- What words with the root thérme do you know?
- What do you use to measure temperatures?
- How do you keep a liquid hot or cold?
- What controls how much heat a furnace delivers to a room?
- What is the medical condition in which a person loses heat faster than the body can produce heat?
Everyday experiences with thermal phenomena may include using thermometers to measure temperatures, storing hot or cold liquids in a thermos, adjusting a thermostat to increase or decrease the amount of heat delivered to a room, and taking care to avoid hypothermia while hiking in cold and/or wet weather.
The formal name for the focus of this unit is thermodynamics. This is the study of energy in the form of heat (thermo) and ways such energy flows within a system (its dynamics). Thermodynamics is the study of what happens when things warm up or cool down.
- Record some of your experiences with thermal phenomena before reading examples of student work.
1. Examples of student work identifying everyday connections to thermal phenomena
A student reflected on relevant resources as follows:
The elementary students in my classroom will experience thermal phenomena in their everyday lives. They will experience the warmth of the sun on their faces, the coldness of metal handrails in the winter, and hot pavement in the summer. Students who take baths may also be aware of what happens when you combine a lot of hot water with some cold water – the water temperature lowers, but is still on the warmer side.
Physics Student, Spring 2015
Another student wrote about an early experience that she had had:
I can remember being a young child and running to be the first in my classroom so that I could get a good seat. The good seat was not only close to the front, but it was a wooden chair, so it did not feel as cold as some of the metal and plastic chairs in the room.
Physics student, Fall 2015
Such memories provide useful examples of thermal phenomena to be explained.
B. Documenting initial ideas with diagnostic questions about thermal phenomena
One way we make sense of the world is through observations, what we see, hear, smell, taste, and feel. These observations provide evidence that we can think about and interpret in different ways. The diagnostic questions below document some of your initial ideas about thermal phenomena and will not be graded.
Diagnostic Questions about Thermal Phenomena
- Consider (without touching) materials you may have at home such as an aluminum pie pan, steel can opener, Styrofoam or paper cup, and wooden salad fork – or four blocks made of such materials: an aluminum block, a steel block, a Styrofoam block or pad of paper, and a wooden block.
Rank these in order of temperature. Explain the reasoning for your predicted ranking.
- Touch the four materials. Rank these in order of temperature.
Explain the reasoning for your ranking.