# PS.7 a, c-d - Thermal Energy

The student will investigate and understand temperature scales, heat, and thermal energy transfer. Key concepts include

a) Celsius and Kelvin temperature scales and absolute zero;

c) conduction, convection, and radiation; and

d) applications of thermal energy transfer.

Bloom's Levels:  Analyze; Understand

### BIG IDEAS

• Energy can be transferred between objects or can be converted into different forms.
• Energy exists in many forms and has the ability to do work or cause a change.

• I can compare the climate of the United States to that of other countries.
• I can explain how the sun heats the earth.
• I can explain how a refrigerator works.

### UNDERSTANDING THE STANDARD

• Heat and temperature are not the same thing. Heat is the transfer of thermal energy between substances of different temperature. As thermal energy is added, the temperature of a substance increases.
• Temperature is a measure of the average kinetic energy of the molecules of a substance. Increased temperature means greater average kinetic energy of the molecules in the substance being measured, and most substances expand when heated. The temperature of absolute zero (–273oC/0 K) is the theoretical point at which molecular motion stops.
• Atoms and molecules are perpetually in motion.
• The transfer of thermal energy occurs in three ways: by conduction, by convection, and by radiation.

### ESSENTIALS

In order to meet this standard, it is expected that students will

a)  distinguish between heat and temperature.

compare and contrast Celsius and Kelvin temperature scales and describe absolute zero.

c)  compare and contrast methods of thermal energy transfer (conduction, convection, and radiation) and provide and explain common examples.

d)  explain, in simple terms, how the principle of thermal energy transfer applies to heat engines, thermostats, refrigerators, heat pumps, and geothermal systems.

design an investigation from a testable question related to thermal energy transfer. The investigation may be a complete experimental design or may focus on systematic observation, description, measurement, and/or data collection and analysis.

### KEY VOCABULARY

Celsius temperature scale, Kelvin temperature scale, absolute zero, heat, temperature, phase change, freezing point, melting point, boiling point, vaporization, condensation, conduction, convection, radiation, heat transfer

Updated: Jun 29, 2018