Kelvin, Celsius, Fahrenheit: Three Types of Temperature Scales

Study Notes

The diagram shows three thermometers, each labeled with boiling point of water, melting point of water, and absolute zero.
The Kelvin scale is the most important scale since it is based on absolute zero.
Absolute zero is -273.15 degrees Celsius.

A change of one degree Celsius is the same as a change of 1.8 degrees Fahrenheit.

Two systems at different temperatures, if placed into contact with another, a higher temperature will transfer heat to the lower temperature.
The system will reach thermal equilibrium, they will then be in the same temperature.

"Zeroth law" states that if two systems are in thermal equilibriums with a third system, they are in thermal equilibriums with each other.

It consists of a bulb containing mercury attached to a glass tube of narrow diameter filled with mercury and a standard temperature scale is marked on the tube.
The boiling point of water and melting point of water.
With changes in temperature, the mercury expands and contracts and the temperature can be read from the scale.

Consists of a glass capillary tube marked with degrees Celsius or Fahrenheit and containing alcohol which rises or falls as it expands or contracts with changes in temperature.

Thermal expansion is the tendency of matter to change in volume in response to changes in temperature.
When a substance is heated, its kinetic energy increases, this increased energy causes the molecules to vibrate more and they are moved further apart from each other.
Thermal expansion can occur in any dimension of an object, with corresponding effects on its volume.
All dimensions of the object expand proportionally to the temperature change.
All materials expand differently depending on the material's structure and properties.
The thermal expansion of solids are categorized into three types: linear, areal, and volumetric.

Is the change in length of an object when subjected to temperature changes, the increase in length is proportional to the original length.
L = L0(1+αΔT)
Where L = final length, L0 = original length, α = coefficient of linear expansion, and ΔT = change in temperature.

The change in the area of a surface when the temperature changes.
A = A0(1+2αΔT)
The coefficient of area expansion of a solid, which is approximately twice the coefficient of linear expansion.

Is defined as the change in volume per unit original volume per unit temperature change.
The change in volume is proportional to the original volume and the change in temperature.
V = V0(1+βΔT)
Where V0 is the original volume, β is the coefficient of volumetric expansion, and ΔT is the change in temperature.

Calorimetry is the branch of thermodynamics that deals with the measurement of heat transfer during physical and chemical processes.
Heat transfer describes the flow of energy between systems at different temperatures.
The amount of heat transferred is: Q = m·c·ΔT.

Heat is a transfer of energy - energy is highly localized.
Heat transfer describes the flow of energy between systems at different temperatures.
The increasing temperature is the increase of kinetic energy in the matter of the object.
The amount of heat transferred is: Q = m·c·ΔT.

The values for the specific heat of some common substances are given in the table.
Specific heat capacity is the amount of heat energy required to raise the temperature of a unit mass of a substance by one degree Celsius.