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How is the randomness measured?
Quote from: Bored chemist on 12/12/2024 11:00:26Quote from: hamdani yusuf on 12/12/2024 00:03:23What's the fundamental difference between gross motion and thermal motion?Direction.What's the direction that makes a motion thermal, and what direction makes it non-thermal?
Quote from: hamdani yusuf on 12/12/2024 00:03:23What's the fundamental difference between gross motion and thermal motion?Direction.
What's the fundamental difference between gross motion and thermal motion?
Quote from: hamdani yusuf on 12/12/2024 20:39:27Quote from: Bored chemist on 12/12/2024 11:00:26Quote from: hamdani yusuf on 12/12/2024 00:03:23What's the fundamental difference between gross motion and thermal motion?Direction.What's the direction that makes a motion thermal, and what direction makes it non-thermal? It's becoming clear that you are either trolling or, I'm afraid, just not bright enough to understand science.I think it would be better all round if you tried something else.If, after literally years of patient explanation, you haven't got to grips with this idea, you probably never will and maybe you should try a different field
How is the randomness measured?If two identical objects have the same total kinetic energy. The first one has more random motion than the second one. Which one has higher temperature?If they're let to exchange their kinetic energy, which one will end up with higher kinetic energy?
Timestamps0:00 Celsius 2:14 Fahrenheit4:42 Kelvin8:00 Lightning Round (Rankinet, R?mer, Delisle, Newton, Reaumur, Wedgwood)? DISCLAIMER ?This video is intended for entertainment and educational purposes only. It should not be your sole source of information. Some details may be oversimplified or inaccurate. My goal is to spark your curiosity and encourage you to conduct your own research on these topics.
Formally they have the same units. J/KPractically they don't, because (for heat capacity) you almost always add an amount soJ/K mol or J/K KgBut for entropy, the "unit" is often "per molecule/ atom " Those entities are countable, and a number is dimensionless.On the other hand, "mole" is also a number.It's a perennial problem in metrology. How do you measure "how much stuff you have".
https://en.m.wikipedia.org/wiki/TemperatureTemperature is a physical quantity that quantitatively expresses the attribute of hotness or coldness. Temperature is measured with a thermometer. It reflects the average kinetic energy of the vibrating and colliding atoms making up a substance.... When two systems in thermal contact are at the same temperature no heat transfers between them. When a temperature difference does exist heat flows spontaneously from the warmer system to the colder system until they are in thermal equilibrium. Such heat transfer occurs by conduction or by thermal radiation.[45][46][47][48][49][50][51][52]Experimental physicists, for example Galileo and Newton,[53] found that there are indefinitely many empirical temperature scales. Nevertheless, the zeroth law of thermodynamics says that they all measure the same quality. This means that for a body in its own state of internal thermodynamic equilibrium, every correctly calibrated thermometer, of whatever kind, that measures the temperature of the body, records one and the same temperature. For a body that is not in its own state of internal thermodynamic equilibrium, different thermometers can record different temperatures, depending respectively on the mechanisms of operation of the thermometers.
No, the temperature of the xenon gas at the top of the 100 km tall isolated tube will not be the same as at the bottom due to the effects of gravity and the barometric temperature gradient.Explanation:1. Hydrostatic Equilibrium:In the presence of gravity, the gas molecules are denser near the bottom and less dense at the top. The pressure decreases with height following the barometric equation:P(h) = P_0 e^{-\frac{m g h}{k_B T}}- P(h) is the pressure at height h, - P_0 is the pressure at the bottom, - m is the mass of a xenon atom, - g is the acceleration due to gravity, - h is the height, - k_B is Boltzmann's constant, - T is the temperature.2. Temperature Gradient:If the tube is adiabatically isolated, the temperature will vary with height due to the adiabatic lapse rate. As gas at the bottom is compressed under high pressure, it is warmer, while gas at the top expands, causing cooling.The temperature change with height is given by:\frac{dT}{dh} = -\frac{g M}{C_p} is the acceleration due to gravity, is the molar mass of xenon (), is the specific heat capacity at constant pressure.For xenon gas, this lapse rate will cause the temperature to decrease with increasing height.3. Key Factors:Isolated Tube: If there is no external heat exchange (adiabatic system), the temperature will follow the lapse rate described above.Non-isolated Tube: If heat can be transferred between the gas and the surroundings, the temperature might equalize over time.Conclusion:The gas temperature at the top will generally be lower than at the bottom in an isolated system due to the adiabatic lapse rate caused by the influence of gravity. For a 100 km tall column, this difference could be significant.
The gas temperature at the top and bottom would not be the same. Here's why: * Pressure Variation: The weight of the gas column creates a higher pressure at the bottom of the tube compared to the top. This pressure difference can affect the gas's internal energy and temperature. * Adiabatic Processes: As the gas moves up the tube, it experiences a decrease in pressure, leading to adiabatic expansion. This expansion causes the gas to cool slightly. Conversely, as the gas moves down the tube, it experiences adiabatic compression, which causes it to warm slightly.While these effects might be subtle, they would still lead to a slight temperature difference between the top and bottom of the tube.However, it's important to note that this is a highly idealized scenario. In real-world conditions, other factors like heat leaks, convection currents, and the specific properties of the gas would further influence the temperature distribution.
The atomic mass of the gas does affect the temperature difference between the top and bottom of the tube. A heavier gas, like Xenon, will create a larger pressure gradient along the height of the tube compared to a lighter gas. This larger pressure gradient will result in more significant adiabatic compression and expansion effects.Therefore, a heavier gas will generally exhibit a larger temperature difference between the top and bottom of the tube compared to a lighter gas under the same conditions.However, it's important to note that other factors, such as the initial temperature and pressure, the specific heat capacity of the gas, and the exact height of the tube, will also influence the magnitude of the temperature difference.
If you truly understand the topic, you should be able to answer my follow up questions.
I could answer it, but I don't see the point.
Scenario 1: Which object has the higher temperature?Temperature is a measure of the average kinetic energy per particle due to random motion (thermal motion).If the first object has more random motion, it means a greater fraction of its total kinetic energy is due to the random motion of its particles, while in the second object, a larger fraction of kinetic energy is associated with ordered motion (e.g., linear or rotational motion).Conclusion: The first object has a higher temperature, as its random kinetic energy (thermal energy) is greater.---Scenario 2: If they exchange kinetic energy, which one ends up with higher kinetic energy?When two objects are allowed to exchange kinetic energy, energy tends to flow from higher temperature to lower temperature until thermal equilibrium is reached.Since the first object has a higher temperature, it will lose some of its random kinetic energy to the second object.However, because both objects started with the same total kinetic energy, the final distribution depends on their energy exchange mechanism:If the energy exchange is purely thermal: The second object will gain more thermal energy, leading to a more equal temperature, but their total kinetic energies will remain the same.If the energy exchange also involves ordered motion: The final distribution may vary, depending on whether some of the ordered motion in the second object is converted to random motion.Conclusion: If the objects are identical and only thermal energy is exchanged, both will have the same total kinetic energy at equilibrium. If ordered motion is involved, the outcome depends on the specifics of the exchange.
Temperature and Kinetic Energy: A Deeper DiveWhich object has a higher temperature?The object with more random motion will have a higher temperature.Temperature is directly related to the average kinetic energy of the particles in a substance. More random motion means a higher average kinetic energy, and thus a higher temperature.What happens when they exchange kinetic energy?When two objects with different temperatures are brought into thermal contact, they will exchange energy until they reach thermal equilibrium. In this case, the object with the higher temperature (more random motion) will transfer some of its energy to the object with the lower temperature.Eventually, both objects will reach the same temperature. This means that the final kinetic energy of both objects will be equal, but distributed differently. The object that initially had more random motion will end up with less random motion, and vice versa.In essence, energy will flow from the hotter object (higher average kinetic energy) to the colder object (lower average kinetic energy) until both objects reach the same temperature.
In thermodynamics, temperature is directly related to the average kinetic energy of the particles in an object, not to the total kinetic energy or the randomness of the motion (which is more related to entropy).Temperature Comparison:Given that both objects have the same total kinetic energy but one has more random motion, the object with more random motion would generally have a higher temperature. This is because more random motion typically means a higher average kinetic energy per particle, even if the total kinetic energy is the same.Kinetic Energy Exchange:When two objects at different temperatures are allowed to exchange kinetic energy, heat will flow from the hotter object to the cooler one until they reach thermal equilibrium. Here:The object with the higher temperature (more random motion) will initially have particles with higher average kinetic energy.As they exchange energy, the heat will flow from the object with higher temperature to the one with lower temperature.Eventually, both objects will reach the same temperature, meaning their average kinetic energies per particle will be equal.Therefore, after the exchange:Neither will have higher kinetic energy; they will share the total kinetic energy in such a way that both have the same average kinetic energy per particle, hence the same temperature.So, to summarize:The object with more random motion initially has a higher temperature.After they exchange energy, both will end up with the same kinetic energy because they will reach thermal equilibrium.
Quote from: Bored chemist on 14/12/2024 13:35:23I could answer it, but I don't see the point.You can't see the point because you haven't learned.
How would they exchange their kinetic energy?
I see that, for example, you still think that quoting chatGPT is somehow useful.
Quote from: hamdani yusuf on 14/12/2024 22:27:16How would they exchange their kinetic energy?By radiative transfer.
I asked them with follow up question. The first object is a stationary warm neodymium magnet, while the second object is a spinning but cooler neodymium magnet. How would they exchange their kinetic energy?