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Vocabulary cards


A measure of the average kinetic energy of the particles in an object.

Thermal Expansion

The increase in volume of a substance due to an increase in temperature.

Absolute Zero

The lowest temperature on the Kelvin scale is O K.


The transfer of energy between objects that are at different temperatures.

Thermal Energy

The total kinetic energy of the particles that make up a substance.

Thermal Equilibrium

The point when both objects reach the same temperature.


The transfer of thermal energy from one substance to another through direct contact.


Substances that conduct thermal energy very well.


Substances that do not conduct thermal energy very well.


The transfer of thermal energy by the movement of a liquid or a gas.


The transfer of energy through matter or space as electromagnetic waves.

Thermal Conductivity

The rate at which a substance conducts thermal energy.

Specific Heat Capacity

The amount of energy needed to change the temperature of 1 kg of a substance by 1° C.


Is used to find the specific heat capacity of a substance.

States of Matter

The physical forms in which a substance can exist.

Change of State

The conversion of a substance from one physical form to another.


Liquid to solid


Solid to liquid


Liquid to gas


Gas to liquid

Steam-Heating System

Is similar to a hot-water heating system, except that steam is used.


A substance that reduces the transfer of thermal energy.

Passive solar heating systems

DO NOT have moving parts. They rely on a building's design and parts.

Active solar heating systems

Do have moving parts. They use pumps and fans to distribute energy throughout the building.

Heat Engine

A machine that uses heat to do work.


Process of how engines burn fuel.

External combustion engines

Heat engines that burn fuel outside the engine.

Internal combustion engines

Heat engines that burn fuel inside the engines.

Thermal Pollution

The excessive heating of a body of water.

Chemical Changes

Can cause thermal energy to be absorbed or released.

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