Ch. 16 Thermal Energy and Heat

Heat

The quality of being hot; high temperature.

Conduction

The transfer of thermal energy through touching with no overall transfer of matter.

Thermal Expansion

Thermal expansion is the tendency of matter to change in volume in response to a change in temperature, through heat transfer. Temperature is a monotonic function of the average molecular kinetic energy of a substance. When a substance is heated, the kinetic energy of its molecules increases.

Waste heat

Waste heat is by necessity produced both by machines that do work and in other processes that use energy, for example in a refrigerator warming the room air or a combustion engine releasing heat into the environment.

Convection current

a current in a fluid that results from convection.

Heat Pump

a device that transfers heat from a colder area to a hotter area by using mechanical energy, as in a refrigerator.

Calorimeter

an apparatus for measuring the amount of heat involved in a chemical reaction or other process.

Internal Combustion Engine

an engine that generates motive power by the burning of gasoline, oil, or other fuel with air inside the engine, the hot gases produced being used to drive a piston or do other work as they expand.

Refrigerant

causing cooling or refrigeration.

Central Heating System

A central heating system provides warmth to the whole interior of a building (or portion of a building) from one point to multiple rooms. When combined with other systems in order to control the building climate, the whole system may be an HVAC (heating, ventilation and air conditioning) system.

External Combustion Engine

An external combustion engine (EC engine) is a heat engine where an (internal) working fluid is heated by combustion in an external source, through the engine wall or a heat exchanger. The fluid then, by expanding and acting on the mechanism of the engine, produces motion and usable work.

Thermal Conductor

In physics, thermal conductivity (often denoted k, λ, or κ) is the property of a material to conduct heat. It is evaluated primarily in terms of Fourier's Law for heat conduction. Heat transfer occurs at a lower rate across materials of low thermal conductivity than across materials of high thermal conductivity.

Temperature

Is a measure of how hot or cold and object is compared to a reference point such as freezing or boiling.

Heat Engine

Is any device that converts heat into work.

Thermodynamics

the branch of physical science that deals with the relations between heat and other forms of energy (such as mechanical, electrical, or chemical energy), and, by extension, of the relationships between all forms of energy.

Radiation

the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization.

Specific Heat

the heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).

Absolute Zero

the lowest temperature that is theoretically possible, at which the motion of particles that constitutes heat would be minimal. It is zero on the Kelvin scale, equivalent to -273.15°C or -459.67°F.

Convection

the movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.

Thermal Insulator

the process of insulating against transmission of heat.