B-2 Physics Topic 2.3 Thermodynamics

The amount of heat required to change a substance's state (solid to liquid or liquid to gas) without changing its temperature. For example, the heat needed to turn water into steam at a constant 100°C.

The specific amount of latent heat required to change one gram of a liquid to one gram of gas at its boiling point.

The specific amount of latent heat required to change one gram of a solid to one gram of liquid at its melting point.

Heat that causes a change in temperature. It is the heat you can feel and measure with a thermometer.

The process where a gas is compressed, causing it to heat up and then release its heat to condense into a liquid.

The process where a high-pressure liquid refrigerant is released through a valve, causing it to rapidly expand and cool.

The process where a refrigerant absorbs heat, causing it to evaporate and cool the surrounding area, like inside a refrigerator.

The cycle of a refrigerant changing states between liquid and gas to transfer heat and cool a space.

The theory that matter is made up of tiny particles constantly in random motion. The faster the particles move, the more heat energy they have.

The increase in volume of a substance when it is heated. This happens because the particles move farther apart.

The increase in length of a substance when it is heated.

Two different metals joined together. When heated, they expand at different rates, causing the strip to bend. This bending is used in various applications.

The ability of a substance to conduct heat. Good heat conductors allow heat to flow through them easily.

The amount of heat required to raise the temperature of a substance by a certain amount.

The change of state from a liquid to a gas.

The process by which a gas turns back into a liquid.

The Celsius scale measures temperature with 100 increments between the freezing point of water (0°C) and its boiling point (100°C).

The Kelvin scale has 100 increments between the freezing and boiling points of water, like Celsius. However, zero Kelvin represents absolute zero, where all molecular activity stops.

Kelvin and Celsius scales share 100 increments. The difference is that Kelvin starts at absolute zero (-273°C). To convert, add or subtract 273.

The Fahrenheit scale measures temperature with 180 increments between the freezing point of water (32°F) and its boiling point (212°F).

To convert between Celsius and Fahrenheit, use these formulas: °F = 9/5 °C + 32 and °C = 5/9 (°F - 32).

Work is calculated by multiplying the force applied by the distance moved.

Power is the rate at which work is done. It's how quickly energy is transferred.

In both piston and gas turbine engines, air is compressed before fuel is introduced and ignited.

The compression process in engines significantly increases the temperature of the air due to increased molecular collisions.

A piston engine converts reciprocating motion (back and forth) into rotary motion (circular) in a four-stroke cycle.

In the intake stroke, air and fuel are drawn into the cylinder.

The compressed fuel-air mixture is ignited by a spark, producing a force that drives the piston down.

The exhaust gases are pushed out of the cylinder by the ascending piston.

A combination of Boyle's and Charles' laws, explaining the relationship between pressure, volume, and temperature of an ideal gas.

The energy associated with heat transfer, loss, or application. It cannot be created or destroyed, only converted between different forms.

States that heat cannot be destroyed but can be converted between different forms of energy, like electrical to mechanical.

States that heat naturally flows from a warmer body to a cooler body, never the other way around.

Heat produced by combustion (burning fuel). Used for beneficial purposes (heating) or unwanted waste (engine heat). Ranges from a match to a power station.

An engine cycle where combustion happens at approximately constant pressure, causing the cycle to be known as the Constant Pressure cycle.

An engine that uses an extra turbine to power a propeller, adding thrust to the aircraft.

An engine where an extra turbine powers a large, shrouded fan, which accelerates air for additional thrust.

An engine that utilises extra turbines to deliver power to various applications, such as generators, ship propellers, and helicopter rotors.

The force that propels an aircraft forward, generated by accelerating a mass of air.

A type of jet engine that accelerates a small mass of air to a high speed, resulting in high exhaust velocity and significant thrust.

A type of propeller engine that accelerates a large mass of air at a lower speed, generating thrust efficiently.

The equation that calculates thrust by multiplying the air mass flow rate by the difference in exhaust and initial air velocity.