Particle model of matter
The particle model imagines matter made up of individual particles (atoms, molecules)!
https://www.youtube.com/watch?v=KBmhSd7wb5Y
The particle model of matter
The central model for the description of thermodynamic processes is the particle model, which will be...
Planck’s law and Wien’s displacement law
Planck's law describes the radiation emitted by black bodies and Wien's displacement law the maximum of the spectral intensity of this radiation.
https://youtu.be/lKoMK30GVrY
Blackbody radiation
The emitted wavelength spectrum of a blackbody as shown...
Why does water boil faster at high altitudes?
Due to the lower pressure, the boiling point of water decreases and the water boils earlier at high altitudes.
https://www.youtube.com/watch?v=-nf8w-SeFDM
Cooking on Mount Everest
With increasing altitude above sea level, the air pressure decreases...
How does a liquid-in-glass thermometer work?
In liquid-in-glass thermometers, the thermal expansion of liquids is used for measuring the temperature!
https://youtu.be/4ZcQ1HQbQwo
Operating principle
Liquid-in-glass thermometers are based on the principle of thermal expansion of substances. A liquid in a glass...
How does a gas filled thermometer (gas-in-metal) work?
In gas thermometers, the pressure rise connected with a temperature increase is used for measuring the temperature!
https://youtu.be/aYpHDEhvzLo
In gas filled temperature gauges (also called gas thermometers or gas-in-metal thermometers), a gas is...
Stefan-Boltzmann law & Kirchhoff’s law of thermal radiation
The Stefan-Boltzmann law states that the radiant power of an object in thermal equilibrium is proportional to the fourth power of temperature and directly proportional to its surface!
https://youtu.be/U67D8q88UDA
Introduction
In the article Blackbody...
How does a bimetallic strip thermometer work?
In bimetallic strip thermometers the different rates of expansion of metals when heated is used to measure the temperature!
https://youtu.be/RFWj7L05Yxo
Operating principle
Temperatures can be meassured based on the principle of different thermal expansion...
How does a liquid filled thermometer (liquid-in-metal) work?
Liquid-in-metal thermometers use the pressure rise of a liquid that comes along with an increase in temperature, if the volume is kept constant!
https://youtu.be/Q7YNHcrrg2o
In liquid-in-metal thermometers (also referred to as liquid filled...
How does a vapor pressure thermometer (vapor-in-metal) work?
Vapor pressure thermometers use the temperature-dependent vapor pressure of a liquid as the measuring principle.
https://youtu.be/K6HYsY6fF8k
The less popular vapour pressure thermometers work according to the same principle as liquid-in-metal thermometers or gas-in-metal...
How does a infrared thermometer (pyrometer) work?
Pyrometers (infrared thermometers) use the heat radiation of objects invisible to the human eye to determine the temperature!
The thermometers presented in the previous articles must directly touch the object from which...
Why does the temperature remain constant during a change of state (phase transition)?
During a change of the state of matter, the supplied energy is not used to increase the kinetic energy of the molecules, but to change the binding energies. Therefore, the temperature...
Different forms of Planck’s law
Planck's law of radiation can be expressed in different forms. The most important ones are discussed in this article.
https://www.youtube.com/watch?v=JxDgEUsgAIs
Introduction
Planck's law of radiation describes the radiation emitted by black bodies. However, there...
How does a resistance temperature detector (resistance thermometer) work?
In resistance thermometers the dependence of the electrical resistance on the temperature is used to determine the temperature!
https://youtu.be/L5I8_AcJ_nE
Operating principle
A further measuring principle for determining the temperature is the change in the...
Temperature and particle motion
The higher the temperature of a substance, the greater the kinetic energy of the particles!
https://youtu.be/nhFTx9B3m7w
Temperature
If matter is heated and thus its temperature rises more and more, it can be seen that...
Final temperature of mixtures (Richmann’s law)
Richmann's law of mixtures describes the final temperature resulting in thermodynamic equilibrium when two bodies with different initial temperatures are brought into contact.
https://youtu.be/6tue9N7M1vU
Adiabatic mixing
If two bodies with different initial temperatures are...
How does a thermocouple work?
In this article we will deal with the design and operation of a thermocouple which is used to measure temperatures.
https://youtu.be/y7efQiLkfkM
Seebeck effect
A thermocouple uses the phenomenon that a voltage is caused by...
Blackbody radiation
Blackbody radiation (cavity radiation) is the thermal radiation of a blackbody, i.e. a body that absorbs all incident radiation.
https://www.youtube.com/watch?v=Na-mFjyP8eU
Blackbody
When white light hits an opaque object, a certain part of that light...
Thermodynamic derivation of the Stefan-Boltzmann Law
In this article the Stefan-Boltzmann-Law is to be derived using the laws of thermodynamics.
https://www.youtube.com/watch?v=oo-A0uGeUlE
Introduction
In this article, the Stefan-Boltzmann Law is to be derived with the laws of thermodynamics. In order to...