Heat transfer / energy

Heat energy

• Thermal energy is the total kinetic energy of a substance's atoms and molecules.
• There are four main changes of state
• Vaporisation: the state of a liquid to a gas
• Condensation: the state of a gas to liquid
• Freezing: the state of a liquid to solid
• Melting: the state of a solid to a liquid
• Atoms and molecules are in a constant motion, and when thermal energy causes them to move apart and move faster it causes a change of state.
• Thermal energy can be transferred in three ways:
• Convection: the heat transfer from the movement of liquids
• Conduction: the heat transfer when two objects are in direct contact
• Radiation: the heat transfer from the electromagnetic waves that travel through space.
• There are four main changes of state
• Vaporisation: the state of a liquid to a gas
• Condensation: the state of a gas to liquid
• Freezing: the state of a liquid to solid
• Melting: the state of a solid to a liquid

Test your knowledge on heat energy

• 1) What is meant by heat transfer?
• Heat transfer is when one substance of a higher temperature transfers its heat to a substance with a lower temperature. This can be done in three ways; conduction, convection and radiation
• 2) Name and define three types of heat transfer
• Conduction: the heat transfer between two objects in direct contact
• Convection: the heat transfer from the movement of liquids
• Radiation: the heat transfer from the electromagnetic waves that travel through space