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Thermodynamics and Statistical Mechanics
Thermodynamics is the study of energy conversion between heat and mechanical work which leads to the macroscopic properties such as temperature, volume, and pressure. Statistical mechanics is the application of probability theory to study the thermodynamic behavior of systems of a large number of particles.
1,125 Questions
The average kinetic energy of the molecules in an object is what law of thermodynamics?
The average kinetic energy of molecules in an object is governed by the first law of thermodynamics, which states that energy cannot be created or destroyed, only transferred or transformed. This is because the kinetic energy of molecules is a form of internal energy that is included in the total energy of the system.
What are the thermodynamic polytropic processes?
Thermodynamic polytropic processes are processes that can be described using the polytropic equation ( PV^n = C ), where ( P ) is pressure, ( V ) is volume, ( N ) is the polytropic exponent, and ( C ) is a constant. These processes can encompass a range of behaviors, from isobaric to isothermal to adiabatic processes, depending on the value of the polytropic exponent.
To find the new diameter of the coin in Death Valley at 48.0°C, you can use the formula for linear expansion: Lf = Li * (1 + α * ΔT), where Lf is the final length/diameter, Li is the initial length/diameter, α is the coefficient of linear expansion, and ΔT is the change in temperature. Plugging in the values, Lf = 1.9 cm * (1 + 2.61e-5 * 48). Calculate to find the new diameter.
How do thermodynamics apply to solar cells?
The first law dictates that the power (energy per unit time) output from a solar cell cannot exceed the power of the light landing on it.
The second law dictates that the efficiency of the solar cell must be less than 100% no matter how good the cell is - some of the energy will be lost as heat output to the surroundings.
Neither has any known exceptions. You do have to account for the equivalence of mass and energy though to keep the 1st law consistent, i.e. E=mc² when it comes to nuclear fission and nuclear fusion.
Which are the most complete books to learn about thermodynamics?
- Engineering Thermodynamics: An Introductory Textbook by Sandeep Agrawal: This comprehensive textbook provides a comprehensive introduction to thermodynamics, covering topics such as energy conversion, entropy, ideal gases, heat transfer, and more. The book features numerous worked examples and problems, and contains a wealth of illustrations to help explain the key concepts.
- Fundamentals of Engineering Thermodynamics by Michael J. Moran, Howard N. Shapiro, and Daisie D. Boettner: This widely-used textbook provides an in-depth look at thermodynamics and its applications. It includes chapters on the properties of pure substances, the first and second laws of thermodynamics, entropy, and more. The book also includes numerous examples and problems with detailed solutions.
- Thermodynamics: An Engineering Approach by Yunus A. Cengel and Michael A. Boles: This popular textbook is written in a style that is easy to understand, and provides an introduction to thermodynamics, along with real-world applications. The book features detailed explanations of topics such as energy, entropy, and the ideal gas law. It also contains a wide range of problems and solutions.
- Thermodynamics and an Introduction to Thermostatistics by Herbert B. Callen: This book provides a comprehensive and rigorous introduction to thermodynamics. It covers topics such as thermodynamic potentials, the first and second laws of thermodynamics, entropy, and more. The book also contains numerous worked examples and problems with detailed solutions.
How perpetual motion device can break the first and second law of the thermodynamics?
It can't. That's the simplest way to explain why no successful perpetual motion machine
has ever been built.
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Another contributor persisted:
well it's just a matter of time and life!
Which of the following are formulations of the second law of thermodynamics?
It isn't possible to change heat completely into work, with no other change taking place.
No system can convert energy from one form to another useful form with 100% efficiency.
It's not possible to transfer heat from an object at a lower temperature to another object at a higher temperature unless work is done.
APEX: Entropy of a system increases over time.
C.No system can convert energy from one form to another useful form with 100% efficiency.It's not possible to transfer heat from an object at a lower temperature to another object at a higher temperature unless work is done.It isn't possible to change heat completely into work, with no other change taking place.
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δQ = T dS (closed system, perfectly reversible process - which doesn't really exisit)
δQ < T dS (closed system, real, irreversible processes)
Rudolph Clausius:
- "Heat can never pass from a colder to a warmer body without some other change, connected therewith, occurring at the same time."
- "It is impossible, by means of inanimate material agency, to derive mechanical effect from any portion of matter by cooling it below the temperature of the coldest of the surrounding objects."
- " Every process occurring in nature proceeds in the sense in which the sum of the entropies of all bodies taking part in the process is increased. In the limit, i.e. for reversible processes, the sum of the entropies remains unchanged."
- "The internal energy of a closed system is increased by an adiabatic process, throughout the duration of which, the volume of the system remains constant."
- "In every neighborhood of any state S of an adiabatically enclosed system there are states inaccessible from S"
The zeroth law of thermodynamics pertains to the concept of thermal equilibrium between two systems. It states that if two systems are each in thermal equilibrium with a third system, then they are in thermal equilibrium with each other. This law establishes the transitivity of thermal equilibrium relationships.
What happens to a substance when it is cooled?
It might cool another fraction of a degree (to -273.15 deg C, approx). No further cooling can take place since at that temperature, there is no longer any atomic vibrational energy left to remove from the substance and so no means to lower the temperature.
Explain the second law of thermodynamics and explain why it is not violated by living organisms?
this increase in organization over time in no way violates the second law. The entropy of a particular system, such as an organism, may actually decrease, so long as the total entropy of the universe-the system plus its surroundings-increases. Thus, organisms are islands of low entropy in an increasingly random universe. The evolution of biological order is perfectly consistent with the laws of thermodynamics.
In thermodynamics the standard pressure is 100.0 kpa . What is this value in units of atmospheres?
1 atm is equal to 101.325 kPa, so 100.0 kPa is approximately 0.9869 atm.
The energy created as a result of the internal combustion equals the amount of energy that was needed to move the automobile. See Below.
The increase in the internal energy of a system is equal to the amount of energy added by heating the system, minus the amount lost as a result of the work done by the system on its surroundings.
aka Conservation of Energy.
Why displacement used in thermodynamics?
Many of the properties measured and calculated in thermodynamics are "state" functions. The key feature is not their absolute value but rather how much they change. We are more concerned with the amount of work required to raise an object 20 feet than we are with the total potential energy of the object. We are more concerned with the change in enthalpy involved with condensing a ton of steam than some absolute enthalpy of the steam. For this reason most thermodynamic properties are tabulated relative to a "reference state". As long as the same reference state is used for both the initial and final conditions, we will always get the same difference between the two, no matter what reference state is chosen. In this respect, we are more interested in how far we are displaced from the reference state as changes are made in a system.
How does temperature difference affect the rate of heat transfer?
- Temperature Difference (.T ) between the two fluids - This is the driving force in heat exchange principles. The greater the .T, the greater the heat transfer rate .
- Fluid flow rate - Increasing flow rate will increase heat transfer rate.
- The nature of the heat conducting materials - Some materials have a high conductivity while others don't. This factor is 'built-in' in the design of the Exchanger and choice of materials. It is governed by the design engineers before manufacture.
- Surface area - The larger the surface area of the conducting interfaces, the greater the heat transfer rate.
The surface area, again, is controlled by the design and manufacture of the exchanger. The more tubes contained in the bundle, the greater the surface area. The tube length will also affect heat transfer, as will the outside diameter and metal thickness of the tubes.
To calculate the frequency of radiation with a wavelength of 9.6 μm, you can use the equation v = c/λ, where v is the frequency, c is the speed of light (3.00 x 10^8 m/s), and λ is the wavelength in meters. First, convert 9.6 μm to meters (1 μm = 1 x 10^-6 m), then plug the values into the equation to find the frequency in s^-1. The frequency corresponding to a wavelength of 9.6 μm is approximately 3.125 x 10^13 s^-1.
What state is propane in a zero degrees Celsius?
At ordinary atmospheric pressures propane is in the gas phase at 0C.
What is needed to move particles from areas of low concentration to high concentration?
Because the concentration is going up so much energy is needed to do this. If the cell was going from a high concentration to a low, no energy is needed because it is already at a high concentration and its going lower you wouldn't need any energy to go lower at a high stance
How is the law of conservation of energy related to efficiency?
Efficiency can never be greater than one because it is the ratio between work you got out of the system and the total energy. Because of conservation of energy, the equation ΔE = Q + W reduces to Q + W = 0.
Does evolution violate the Second Law of Thermodynamics?
No, evolution does not violate the Second Law of Thermodynamics.
No life disobeys the Second Law. Zygotes become embryos, embryos become foetuses, foetuses become babies, then children, then adults. All zygote-to-adult growth fails to disobey the Second Law. There is a constant influx of energy into the growing individuals through nutrition. All life carries out nutrition. There is always energy available for growth and reproduction and if there is enough energy for that, then there is enough energy for change/evolution. In this sense, Law-disobeying complexity is not added, from prokaryote to eukaryote or even from bacterium to human. It is simply growth from neonate-form to adult and there is certainly enough energy for that.
What statement best describes the second law of thermodynamics?
The entropy of the universe is increasing
What does the second law of thermodynamics say apex?
The second law of thermodynamics states that the total entropy of an isolated system can never decrease over time. It implies that processes occur in a direction that increases the overall disorder or randomness of a system. This law helps to explain phenomena such as heat flowing from hot to cold objects and why perpetual motion machines are impossible.
6CO2 + 6H2O -> C6H12O6 + 6O2
The total mass on each side of the formula is the same (372), therefore mass has been conserved.
If you calculate the energy of the bonds on each side of the equation, and the energy given to the system by the light, energy should also be conserved.
Is forbidden based on the second law of thermodynamics?
It forbids heat to move from a cold region to a hot regions spontaneously (you have to "pump" it there - meaning you have to do work to get it to move that direction). Alternatively - it forbids any natural/spontaneous process to DECREASE the entropy of the universe.
True. The first law of thermodynamics, also known as the law of conservation of energy, states that energy cannot be created or destroyed, only transferred or converted from one form to another.
