# What is Temperature?

### Guiding Question

What is Temperature?

## Objectives

#### Concept:

Temperature is the measure of the average kinetic energy of the molecules of a substance.

#### Principles:

• Kinetic energy is energy associated with motion.
• When molecules are moving, there is kinetic energy.
• Hot molecules move faster than cold molecules.

#### Skills:

• Making Observations
• Making Comparisons
• Communicating Findings
• Making Inferences
• Controlling Variables
• Drawing Conclusions
• Making Generalizations

### Materials

1. Large work area
2. Handout

### Room Preparation

Type of Activity: Large Group
Have students move desks out of the center of the room so they have a large open space to move around and work in.

### Safety Precautions

Be careful not to hit anyone! The students will be standing very close to one another.

## Procedures and Activities

### Introduction

Ask, "What is temperature?" Share that:

1. Temperature is the measure of the average kinetic energy of the molecules in a substance. (Kinetic energy is the energy of motion.)

2. The more kinetic energy a molecule has, the faster it is moving.

3. Hot molecules move faster than cold ones.

Today, you will experience "temperature" by pretending to be molecules.

### Activity

1. Have students stand as close to each other as they can without touching each other.

2. Explain to students that they are behaving like the low-energy molecules in a cold substance.

3. Have students increase their level of kinetic energy by walking and moving around.

4. As students increase their kinetic energy, you should notice them spreading out and taking up more space on the floor. Have them pick up pace by jogging around.

5. Have students stop moving and observe their placement after walking and jogging.

6. Like moving molecules, they are now spread out.

7. Have students "see and feel" the increased temperature they have created from movement.

### Discussion

Help students discover that as substances heat up, their molecules speed up and spread apart, causing the substance to expand. Compare this to their movement—standing still, walking, and jogging. This expansion makes the substance less dense, which is why hot air rises. (Note: In reality, the molecules bounce off of each other while moving around. We have asked the students to abstain from that both to make the activity a little safer and to encourage the students to spread out.)

## Closing - Original Question

What is Temperature?

## Evaluation

1. Have students answer the questions on the Handout.

2. Listen for evidence that students understand concepts of temperature, molecules, and kinetic energy.

## Careers Related to Lesson Topic

• Meteorologist
• Tour, Weather Underground at University of Michigan's Department of Atmospheric, Oceanic, and Space Sciences
• Pilot
• TV or Radio Weather Reporter

Let us know what you think!

Mark Palmer
University of Oklahoma
Center for Analysis and Prediction of Storms
(405)-325-6079
mpalmer@ou.edu

Webmaster (Martha)

## Prerequisite Vocabulary

Energy
Useable power.

Kinetic Energy
Energy associated with motion.

Molecules
The smallest particle of a substance that retains all the properties of the substance and is composed of one or more atoms.

Measure of the average kinetic energy of the molecules of a substance.

Updated 18 Jan 01