Download Reflection – Investigating the Temperature of Air 4

Reflection – Investigating the Temperature of Air 4.1
A. How did the temperature of each container of water affect the temperature of the air above it?
The hot water heated the air directly above it. This means that the temperature of
Thermometer B probably rose higher than the temperature of Thermometer A in the
Convection Tube with the hot water, the cold water made the temperature of Thermometer B
drop.
B. The movement of heat is called heat transfer. Describe the heat transfer between the
container of hot water and the air. Describe the heat transfer between the container of cold
water and the air.
Heat energy always moves form warm materials to cooler ones. Therefore, heat moved from
the warm water to the cooler air, which heated the air, and from the warm air to the cooler
water, which heated the water and cooled the air.
C. Under what conditions was it difficult to see through the cylinder? Why do you think this
happened?
The inside of the tube with hot water “fogged up because moisture formed on the inside of
the convection tube. More condensation took place with hot water than with cold water
because of greater evaporation from the container of hot water.
D. Why do you think covering the container helped keep the cylinder clear?
The plastic reduced evaporation by blocking the escape of water vapor.
Reflection – Investigating how Warm and Cool Air Move 4.2
A. On the basis of your temperature readings in inquiry 4.1, how does the temperature of a
surface affect the temperature of the air above it?
Air takes on the temperature of the surface beneath it.
B. How did the air, which was visible because of the smoke, move in the Convection Tube when
the water under it was cold? Explain why you think this happened.
The cold air moved down in the tube. The air looked thick and heavy. Heavy, dense air sinks.
C. What happened to the air in the convection tube when the water was hot? Why do you think
this happened?
The hot air rose quickly in the cylinder. The air looked wispy and light. Light, less dense air
rises.
D. Why do you think moisture formed on the inside of the convection tube with hot water? How
do you think this relates to cloud formation on earth?
The energy needed to evaporate water-that is, to change it from a liquid to a gas-came from
the hot water. The process of liquid water changing to water vapor is called evaporation.
When water vapor rises to high altitudes where the air is cold, it changes into liquid or ice.
This process is called condensation. The moisture in the tube formed when the rising water
vapor met the cool surface of the cylinder and changed back to water, which is similar to cloud
formation.
E. Apply what you observed in lesson 4 to the earth. If the earth’s surface is cold, what will
happen to the air above it? If the surface is hot, what will happen to the air above it?
If the earth’s surface is cold, the air above it will lose heat energy to the cold surface below
and remain close to the surface, If the surface is warm, the air above it will be heated. Warm,
moist air rises, changes to water vapor, forms clouds at higher altitudes, and may fall to the
earth as precipitation.