Energy, Thermal Energy, and Heat Transfer

Vocabulary flashcards covering key definitions, thermal concepts, energy conservation laws, and experimental setups from Chapter 12: Energy.

Thermal energy

Also called heat energy, it is a measure of the total kinetic (movement) energy of the atoms and molecules of a substance due to its internal energy.

Heat

A form of energy that can be transferred from one object to another.

Temperature

An indication of how hot or cold an object is, measured with a thermometer, which reflects the average kinetic energy of the particles hitting the bulb.

Joulemeter

An instrument used to measure the quantity of electrical energy supplied, which equals the amount of heat energy supplied by an electric heater.

Conservation of energy

The principle stating that energy is neither created nor destroyed, but simply moves from one form to another.

Exothermic reactions

Chemical reactions in which energy is released as heat and sometimes also as light into the surroundings.

Endothermic reactions

Chemical reactions in which energy is taken from substances in the surroundings and stored in the products.

Insulators

Materials that reduce the loss of heat energy because they are poor conductors and trap air.

Sea of electrons

Outer shell electrons lost by metal atoms that flow freely around the atoms, binding them together and carrying electricity and thermal energy through the metal.

Electrical energy measurement setup with a joulemeter

An experimental arrangement using a $12\text{ volts a.c. supply}$, an electric heater inserted into a sealed, insulated container of liquid or solid, and a joulemeter to measure heat supplied.

Thermal conduction experiment with a metal rod

An experimental setup where drawing pins are attached to a metal rod with wax; as one end of the rod is heated, thermal energy conducts along the metal and sequentially melts the wax.