Thermal Definition and 1000 Threads

Hello, thank you for taking the time to read this.. I hope I followed the formatting correctly and this post complies with the expectations of the forum. I solved the equation but my answer seems too low. I tried it again and arrived at the same answer. I also had doubts if it was acceptable...

I'm wondering if the outside color has an influence on the thermal depletion of things such as a thermos, a wall, etc. Assuming, obviously, there's no sunlight hitting on them. It certainly has, but what difference percentage can we typically expect for example for bottles such as the ones on...

Suppose we define our system to contain a few deformable bodies that exert gravitational forces on each other, and are consequently moving towards each other in some vague sense. We might want to express the total energy of the system as the sum of the mechanical energy and internal energy...

If a substance gains energy, it's molecules vibrate faster and thus the material increases temperature. My question is if heat lost through any other means but radiation is zero, how exactly does these molecules radiate photons?

Isn't it both use the same exact principle? An infrared thermometer versus a thermal imager? Why is it that the thermal imager is not for body temperature (as indicated below) while the infrared thermometer is for body temperature. I think they both scan the same blackbody of the physical body.

Assume there is a boundary separates two medium with different heat conductivity [κ][/1] and [κ][/2]. In one medium, the temperature distribution is [T][/1](r,θ,φ) and on the other medium is [T][/2](r,θ,φ). What is the relationship between [T][/1] and [T][/2] ? Is it - [κ][/1]grad [T][/1]=-...

If thermal motion (collision of atoms) changes the direction of an atom, will that change the direction of spin? If so, how much time does it take from the change in the atom orientation to the change in the spin?

Hi all, For area expansion, I know the equation goes like: Hence, my answer to part i is ##\begin{aligned}A=A_{0}\left( 1+2\alpha \Delta T\right) \\ = 52\left( 1+2*24\times 10^{-6}\right) \left( 100\right) \\ =52.2496cm^{2}\end{aligned} ## Now I am unsure how to proceed with part 2 in this...

Hello, I'd like some clarification with the exact wording of Kirchhoff's law of thermal radiation. The law states that at thermal equilibrium αλ=ελ. However sometimes I read that absorptivity= emissivity and sometimes I read that rate of A. = rate of E. Which one is correct? I'm not sure but I...

Summary:: In need of help determining the exhaust velocity of a rocket nozzle given temperature and propellant molar mass Greetings and salutations! My name is Robert DeVries, world builder extraordinaire. I have come with questions in search of answers. So for the last few days I've been...

Hi, I would like to know what are all the possible causes of thermal stress. The most common are external constraints that block thermal expansion/contraction (for example a bar fixed at both ends). However I know that there are also at least two additional causes of thermal stress and that...

Hello, I've searched a bit about about the thermal radiation behavior of non-black body and I'm confused. I've read that the color is dependent only on the temperature so every thing display the same color as a black body. But at the same time I've read that materials don't always follow the...

Hello, I'm working with a thermal property measurement tool (KD2 pro). The manual provide the equations used to measure temperature but I'm not sure that I understand them correctly. Temperature during heating (equation 1) T= m0 + m2t + m3 ln(t) Temperature during cooling (equation 2) T= m0 +...

There is this one problem from past exam papers which I cannot seem to do: The air in a kitchen has pressure 1.0 x 10^5 Pa and temperature 22'C. A refrigerator of internal volume 0.36 m^3 is installed in the kitchen. (a) With the door open the air in the refrigerator is initially at the same...

I have already discussed the ontology problem of thermal interpretation (TI) of quantum mechanics (QM) several times in the main thread on TI. The following is supposed to be the final refined version of my argument, so I don't want it to be lost among other posts in the main TI thread...

ΔL= αLoΔT ΔL = (23*10^-6)(0.2480 m)(28.30°C) ΔL = 1.61 * 10^-4 Period is 1s, so each second the pendulum moves 1.61 * 10^-4 m 1.61 * 10^-4 m/s *(60s/1min)*(60min/1hr)*(24hr/1day) = 13.95 m/day T = s (1:1 ratio) 13.95 seconds. But the answer is actually 69.3 s. Is the equation T = 2π√L/g...

Here is the Q below I want to see if my values for part b) is okay? This is what I have tried: Any help would be nice! Thanks

in the inside of the material is heat also can transferred by radiation?

Inside a CPU, when applying voltage to the gates of the CMOS transistor(high input), are the gate ore another components of a transistor will generate thermal radiation which will be absorbed by the neighboring transistor?

I don't know what to do!

I am trying to find out where to get the Thermal coefficient of expansion for glycerin. The only thing I keep getting when using Google is mathematical examples that use glycerin as an example and its coefficient but I need to know where this number is coming from. Ex: 4.85 × 10^-4 (°C)-1

[Moderator's note: Thread spun off from previous thread due to topic change.] The thermal interpretation of the double slit experiment is very appealing alternative explanation to the Bohmian interpretation as I understood it from these discussions...

So this is a problem from the legendary Razavi book "Design of Analog CMOS Integrated Circuits" (Specifically, it is the problem 7.7 (c)). I got the solutions online but when I try to calculate the noise expression myself, I don't arrive at the same result. Lambda is assumed zero for neglecting...

When ICs undergo accelerated testing via thermal cycling, wouldn't rate of temperature increase factor into the equation? For example, in Equation 4 in this pdf: http://www.issi.com/WW/pdf/semiconductor-reliability.pdf The Temp Cycling Acceleration Factor is a function of Tmax,stress and...

##\Delta V = \beta V \Delta T####\rho _2 = \frac m {V + \Delta V} = \frac { \rho V} {V(1+\beta \Delta T)} = \frac \rho {1+\beta \Delta T}## ##\Delta \rho = \rho _2 - \rho = \frac \rho {1+\beta \Delta T} - \rho = \rho (\frac 1 {1+\beta \Delta T} - 1) = \rho \frac {-\beta \Delta T} {1+\beta \Delta...

Hi, I'm working on a project for a thermal fluids design class in which a theoretical Thorium reactor is to be designed and modeled, and I'm a little bit at a loss for how to start analyzing the problem. I know the system will have 4 fluid systems: an enriched FLiBe system connected via HX to...

I do not understand how this formula is derived: Can somebody help me? Source: https://www.corzan.com/en-us/piping-systems/specification/thermal-expansion

Hello, I'm slowly getting crazy about this stuff. I'm trying to understand what are thermal inertia/effusivity and information have been incoherent so far. The best example of that is seen on wikipedia where the only mention of thermal inertia is in the article...

Any object with a temperature emits corresponding EM waves. Thermal imaging works by considering our temperature of 37C/98.4F/310K, and it corresponds to 9.3um LWIR as per Wien's law. I was thinking about the following summer scenarios in which how it would work. 1) If...

Hello, I was pondering on the well known fact that a certain amount of substance, when absorbing heat, increases in temperature up to a certain temperature and then phase (state) transformation takes place. Any energy supplied at that point does not increase the temperature any further but is...

Hello, Internal energy is the sum of the total KE and total PE of the system. Thermal energy is essentially representing the KE of the system and depends on temperature. When studying heat engines, we learn that it is better, in the name of efficiency, to get the same 1000 J of thermal energy...

Overall thermal conductivity? for example, there are 3 layers made of different materials, having different thermal conductivities bonded with each other; conductivity of layer 1= k_1 = 1 W/m-K thickness of layer 1= t_1 = 0.004 m conductivity of layer 2= k_2 = 148 W/m-K thickness of layer 2=...

Concerning p.198 of Bell's famous 1964 paper http://cds.cern.ch/record/111654/files/vol1p195-200_001.pdf How does TI explain Bell's move from the first equation to the second equation? Under TI, what is the physical significance of this move? Thank you.

This is how I solved part a) : ##Q_1=C\cdot (T_1-T_i)## This quantity is negative because object 1 loses heat. (positive for the machine) ##Q_2=C\cdot (T_2-T_i)## This one is positive because the object 2 absorbs heat.(negative for the machine) Then the exchanged heat FOR THE MACHINE is...

[Moderator's note: Spin off from previous thread since this is a separate topic from that one.] It's hard to expect that it ever gets a standard interpretation, because it contradicts the very observations which lead to the discovery of modern quantum including Born's probability interpretation...

We can write our radius as a function of the height, z, of our cone: $$R(z) = \frac{R_2 - R_1}{h} z + R_1$$ Where h is the height of our cone, ##h = \frac{L}{40}##. Our cross sectional area, $$A = 2 \pi R t$$ can then be written as $$A = 2 \pi t [\frac{R_2 - R_1}{h} z + R_1]$$ This I am all...

This is a repost as I didn't read the community guidelines the first time. Hopefully this is better! First thing I did was write down both the linear and volume expansion formulas. I then multiplied my alpha by 3 and used the volume expansion equation for both materials. ∆V oil > ∆V pot, at the...

Summary: Help with volume and length expansion question Hi, I am struggling with this question. I understand that beta = 3 alpha so you use this to sub into the volume expansion equation. Is this correct? Can someone please provide a step by step instruction on how to do this question? Thank you !

A coal fired steam plant takes in feed water at a temperature of 70°C and produces 15 tonnes of steam per hour at a pressure of 60 bar and temperature 400°C. The fuel consumption rate is 1.5 tonnes per hour and the calorific value of the fuel is 40MJkgˉ¹. Determine the power rating of the boiler...

I'm a mathematician with a longstanding interest in physics, and I've recently been enjoying reading and thinking about Arnold Neumaier's thermal interpretation, including some threads on this forum. There's something that's still confusing me, though, and I'm hoping someone here can clear it...

I worked on a lab experiment that was meant to measure heat capacity but left me with some other questions. The students measured the mass of a cup of liquid nitrogen as it boiled off, recording mass vs time. Then they drop a solid object into the bath, one experiment with a small bit iron...

So I started from the heat governing equation above. There is no heat generation or matter flow, so I simplified it to dT/dt = A d^(2)T/dx^(2). Now I assume dT/dt = (278.15K-277.38K)/(1200s-900s) = 0.0025667. But then I'm stuck with the d^(2)T/dx^(2). Is the x just 0.20 m? For T I used 288.15K...

Ref: Palsson, Halldor | Analysis of Numerical Methods for Simulating Temperature Dynamics in District Heating Pipes - please check pg. 62 at LINK (CLICK!) INTRO: In this reference, the mutual thermal resistances between layers as water-insulation, ground-surrounding, and insulation-ground are...

Hi All, Considering a set of many many small hard balls which start colliding inside a box. The velocities of these balls being mostly greater than c/2. Is it possible, in this case, to speak of convergence to a thermal state in the same sense of ordinary thermodynamics (i.e., using...

Smolin latest book about the quantum is quite interesting. Its called "Einstein Unfinished Revolution: Search for What Lies Beyond the Quantum" and he has a new theory or interpretation. Id like to know what you make of it. The theory is very simple. Similar views produce QM. May i know how this...

BACKGROUND, skip if you want: I'm repairing the amps (2) and power supply for a 1970's era Rhodes Electric Piano (for my local HS music depart). Since this is a classic instrument, I found plenty of info, so the rebuild went well, but I'm curious about one thing, and want to check my...

## \Omega(E_1)## is the number of microstates accessible to a system when it has an energy ##E_1## and ##\Omega(E_2)## is the number of microstates accessible to the system when it has an energy ##E_2##. I understand that each microstate has equal probability of being occupied, but could...

I just finished a 4th part of my series of papers on the thermal interpretation: Foundations of quantum physics IV. More on the thermal interpretation This paper continues the discussion of the thermal interpretation of quantum physics. While Part II and Part III of this series of papers...

In any quantum system, the differences of the energy levels (the eigenvalues of the Hamiltonian ##H##) are in principle directly observable, since they represent excitable oscillation frequencies of the system and thus can be probed by coupling the system to a harmonic oscillator with adjustable...