User:Aclifton6: Difference between revisions

From Physics Book
Jump to navigation Jump to search
(Thermal Energy)
 
 
(12 intermediate revisions by the same user not shown)
Line 1: Line 1:
==Thermal Energy==
==Thermal Energy==


This topics focuses on energy work of a system but it can only deal with a large scale response to heat in a system. '''Thermodynamics''' is the study of the work, heat and energy of a system.  The smaller scale gas interactions can explained using the kinetic theory of gases. There are three fundamental laws that go along with the topic of thermodynamics.  They are the zeroth law, the first law, and the second law. These laws help us understand predict the the operation of the physical system. In order to understand the laws, you must first understand thermal equilibrium.  [[Thermal equilibrium]] is reached when a object that is at a higher temperature is in contact with an object that is at a lower temperature and the first object transfers heat to the latter object until they approach the same temperature and maintain that temperature constantly. It is also important to note that any thermodynamic system in thermal equilibrium possesses internal energy.
This topics focuses on the energy and work of a system. Energy transfer is one of the fundamental principals of Physics, thermal energy falls under this category. This type of energy falls under the abbreviation of Q which stands for the heat that is expelled from an object once a reaction or kinetic energy is transferred; as well as the movement of tiny particles within the object. There are three forms of Thermal Energy: Conduction, Convection and Radiation. Conduction is the transfer of heat energy though collisions between adjacent molecules. Convection is the transfer of heat through motion of a fluid such as air or water; when the fluid is heated it is caused to move away from the source of heat, therefore carrying the heat energy with it. Radiation is the transfer of heat through waves or particles through a material or space.


===Zeroth Law===
===Definitions===


The zeroth law states that if two systems are at thermal equilibrium at the same time as a third system, then all of the systems are at equilibrium with each other. If systems A and C are in thermal equilibrium with B, then system A and C are also in thermal equilibrium with each other. There are underlying ideas of heat that are also important. The most prominent one is that all heat is of the same kind.  As long as the systems are at thermal equilibrium, every unit of internal energy that passes from one system to the other is balanced by the same amount of energy passing back.  This also applies when the two systems or objects have different atomic masses or material. 
E(total) = delta K + delta U + Rest Energy
[https://s-media-cache-ak0.pinimg.com/736x/2a/5e/d6/2a5ed64011dd8c93ecf6bdccca3ba537.jpg]


====Fundamental Principle====
====Units====


If A = B and A = C, then B = C
All types of energy are expressed in Joules. Thermal Energy(Heat) is no different from the other forms of energy with the expression of units; therefore Thermal Energy(Heat) is also expressed in Joules as well.
A = B = C


====A Computational Model====
====A Computational Model====


How do we visualize or predict using this topic. Consider embedding some vpython code here [https://trinket.io/glowscript/31d0f9ad9e Teach hands-on with GlowScript]
You are able to view the transfer of heat through the link provided.[https://www.youtube.com/watch?v=pnVVJfUMkAo.] This link gives credit to the author, Andi Lucas; it is a video I found interesting and entertaining, however I did not create the video.


===First Law===
===First Law===


The first law of thermodynamics defines the internal energy (E) as equal to the difference between heat transfer (Q) ''into'' a system and work (W) ''done by'' the system.  Heat removed from a system would be given a negative sign and heat applied to the system would be given a positive sign. Internal energy can be converted into other types of energy because it acts like potential energy.  Heat and work, however, cannot be stored or conserved independently because they depend on the process.  This allows for many different possible states of a system to exist. There can be a process known as the adiabatic process in which there is no heat transfer.  This occurs when a system is full insulated from the outside environment.  The implementation of this law also brings about another useful state variable, '''enthalpy'''. 
Heat Energy transfer falls under the Law of Thermodynamics. This is defined as the internal energy (E) which is equal to the change of heat transfer (Q) ''into'' a system and work (W) ''done by'' the system.  When heat is removed from a system it results with a negative answer, and when heat is added to a system allows for a positive transfer of heat and thus a positive answer. Heat can not be stored like Potential energy, due to the process that is needed; thus resulting in Kinetic energyDue to this many different arrangements of the system are able to exist.


====A Mathematical Model====
==Specific Heat==


E2 - E1 = Q - W
With liquids and solids that are changing temperature, there is a specific heat associated with a temperature change. This means that the specific heat is variable upon the mass of an object, the change in time as well as the material that is absorbing or expelling heat.


==Second Law==


The second law states that there is another useful variable of heat, entropy (S).  Entropy can be described as the disorder or chaos of a system, but in physics, we will just refer to it as another variable like enthalpy or temperature.  For any given physical process, the combined entropy of a system and the environment remains a constant if the process can be reversed.  The second law also states that if the physical process is irreversible, the combined entropy of the system and the environment must increase.  Therefore, the final entropy must be greater than the initial entropy. 
===Specific Heat Formulas===


===Mathematical Models===
Q= m*c *(change in time)


delta S = delta Q/T
Within this equation heat is found by mass* "C" which is a constant multiplied by the change in time.
Sf = Si (reversible process)
Sf > Si (irreversible process)
 
===Examples===
 
'''Reversible process''': Ideally forcing a flow through a constricted pipe, where there are no boundary layers. As the flow moves through the constriction, the pressure, volume and temperature change, but they return to their normal values once they hit the downstream.  This return to the variables' original values allows there to be no change in entropy.  It is often known as an isentropic process. 
 
'''Irreversible process''': When a hot object and cold object are put in contact with each other, eventually the heat from the hot object will transfer to the cold object and the two will reach the same temperature and stay constant at that temperature, reaching equilibrium.  However, once those objects are separated, they will remain at that equilibrium temperature until something else acts upon it.  The objects do not go back to their original temperatures so there is a change in entropy.


==Connectedness==
==Connectedness==
#How is this topic connected to something that you are interested in?
#How is this topic connected to something that you are interested in?
            This topic is interesting to me because thermal heat was the most enjoyed topic that was studied all semester.
#How is it connected to your major?
#How is it connected to your major?
            My major is Building Construction and this is related because we calculate the change in heat within expansion joints for concrete.
#Is there an interesting industrial application?
#Is there an interesting industrial application?
            The application applied relates to all materials used in construction with expansion and contraction.


==History==
==History==


Thermodynamics was brought up as a science in the 18th and 19th centuries. However, it was first brought up by Galilei, who introduced the concept of temperature and invented the first thermometer.  G. Black first introduced the word 'thermodynamics'.  Later, G. Wilke introduced another unit of measurement known as the calorie that measures heat.  The idea of thermodynamics was brought up by Nicolas Leonard Sadi Carnot. He is often known as "the father of thermodynamics".  It all began with the development of the steam engine during the Industrial Revolution. He devised an ideal cycle of operation.  During his observations and experimentations, he had the incorrect notion that heat is conserved, however he was able to lay down theorems that led to the development of thermodynamicsIn the 20th century, the science of thermodynamics became a conventional term and a basic division of physics.  Thermodynamics dealt with the study of general properties of physical systems under equilibrium and the conditions necessary to obtain equilibrium.
The idea of thermodynamics was idealized during the late 17th century, but was truly recognized during the 18th and 19th centuries. Jean Baptiste Biot (1774-1862) worked on the analysis of heat conduction, however unsuccessful. Then Baron Jean Baptiste Joseph Fourier (1768-1830) continued the work of Boit and completed his(Fourier's) masterpiece which was known as the mathematical theory of heat conduction which was stated within  Theorie Analytique de la Chaleur (1822). "Around 1850 Rudolf Clausius and William Thomson (Kelvin) stated both the First Law - that total energy is conserved - and the Second Law of Thermodynamics. The Second Law was originally formulated in terms of the fact that heat does not spontaneously flow from a colder body to a hotter." The terminology, "thermodynamics", was not created until the year 1854, during this time a British mathematician and physicist, William Thomson (Lord Kelvin) created the terminology thermo-dynamics when he wrote a paper upon On the Dynamical Theory of Heat.


== See also ==
== See also ==
Are there related topics or categories in this wiki resource for the curious reader to explore?  How does this topic fit into that context?
===Further reading===
Books, Articles or other print media on this topic


===External links===
===External links===


Internet resources on this topic
http://www.seas.ucla.edu/jht/pioneers/pioneers.html
http://teacher.pas.rochester.edu/phy121/lecturenotes/Chapter17/Chapter17.html


==References==
==References==


https://www.grc.nasa.gov/www/k-12/airplane/thermo0.html
Georgia Tech Physics Department Example Page
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/thereq.html
http://physics.bu.edu/~duffy/py105/notes/Heattransfer.html
https://www.grc.nasa.gov/www/k-12/airplane/thermo2.html
https://en.wikipedia.org/wiki/Heat_transfer
http://www.phys.nthu.edu.tw/~thschang/notes/GP21.pdf
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatra.html
http://www.eoearth.org/view/article/153532/
https://s-media-cache-ak0.pinimg.com/736x/2a/5e/d6/2a5ed64011dd8c93ecf6bdccca3ba537.jpg
https://www.youtube.com/watch?v=pnVVJfUMkAo


[[Category:Which Category did you place this in?]]
[[Category:Thermal Energy]]

Latest revision as of 21:38, 5 December 2015

Thermal Energy

This topics focuses on the energy and work of a system. Energy transfer is one of the fundamental principals of Physics, thermal energy falls under this category. This type of energy falls under the abbreviation of Q which stands for the heat that is expelled from an object once a reaction or kinetic energy is transferred; as well as the movement of tiny particles within the object. There are three forms of Thermal Energy: Conduction, Convection and Radiation. Conduction is the transfer of heat energy though collisions between adjacent molecules. Convection is the transfer of heat through motion of a fluid such as air or water; when the fluid is heated it is caused to move away from the source of heat, therefore carrying the heat energy with it. Radiation is the transfer of heat through waves or particles through a material or space.

Definitions

E(total) = delta K + delta U + Rest Energy [1]

Units

All types of energy are expressed in Joules. Thermal Energy(Heat) is no different from the other forms of energy with the expression of units; therefore Thermal Energy(Heat) is also expressed in Joules as well.

A Computational Model

You are able to view the transfer of heat through the link provided.[2] This link gives credit to the author, Andi Lucas; it is a video I found interesting and entertaining, however I did not create the video.

First Law

Heat Energy transfer falls under the Law of Thermodynamics. This is defined as the internal energy (E) which is equal to the change of heat transfer (Q) into a system and work (W) done by the system. When heat is removed from a system it results with a negative answer, and when heat is added to a system allows for a positive transfer of heat and thus a positive answer. Heat can not be stored like Potential energy, due to the process that is needed; thus resulting in Kinetic energy. Due to this many different arrangements of the system are able to exist.

Specific Heat

With liquids and solids that are changing temperature, there is a specific heat associated with a temperature change. This means that the specific heat is variable upon the mass of an object, the change in time as well as the material that is absorbing or expelling heat.


Specific Heat Formulas

Q= m*c *(change in time)

Within this equation heat is found by mass* "C" which is a constant multiplied by the change in time.

Connectedness

  1. How is this topic connected to something that you are interested in?
           This topic is interesting to me because thermal heat was the most enjoyed topic that was studied all semester.
  1. How is it connected to your major?
            My major is Building Construction and this is related because we calculate the change in heat within expansion joints for concrete. 
  1. Is there an interesting industrial application?
            The application applied relates to all materials used in construction with expansion and contraction.

History

The idea of thermodynamics was idealized during the late 17th century, but was truly recognized during the 18th and 19th centuries. Jean Baptiste Biot (1774-1862) worked on the analysis of heat conduction, however unsuccessful. Then Baron Jean Baptiste Joseph Fourier (1768-1830) continued the work of Boit and completed his(Fourier's) masterpiece which was known as the mathematical theory of heat conduction which was stated within Theorie Analytique de la Chaleur (1822). "Around 1850 Rudolf Clausius and William Thomson (Kelvin) stated both the First Law - that total energy is conserved - and the Second Law of Thermodynamics. The Second Law was originally formulated in terms of the fact that heat does not spontaneously flow from a colder body to a hotter." The terminology, "thermodynamics", was not created until the year 1854, during this time a British mathematician and physicist, William Thomson (Lord Kelvin) created the terminology thermo-dynamics when he wrote a paper upon On the Dynamical Theory of Heat.

See also

External links

http://www.seas.ucla.edu/jht/pioneers/pioneers.html http://teacher.pas.rochester.edu/phy121/lecturenotes/Chapter17/Chapter17.html

References

Georgia Tech Physics Department Example Page http://physics.bu.edu/~duffy/py105/notes/Heattransfer.html https://en.wikipedia.org/wiki/Heat_transfer http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatra.html https://s-media-cache-ak0.pinimg.com/736x/2a/5e/d6/2a5ed64011dd8c93ecf6bdccca3ba537.jpg https://www.youtube.com/watch?v=pnVVJfUMkAo