What is the equation to calculate the temperature at a given distance from a heat source (inside a green house)? Example: I want to calculate the temperature at 2m, 3m, 5m, 7m from the heating object like a heater.
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Summary: Calculate the air change rate required to keep a certain temperature
In question d above, you were asked to calculate how long the air flow in the system would be active in a day. Now factor in...
I assume that as time is moving much slower on the ship and that may affect the frequency of heat radiation. I am not sure how to phrase the question because I do not want to assume any answers. I did ask Mr. Google but no results.
On 23rd July, 2018, physicists from Indian Institute of Science (IISc) Bangalore, said that they had discovered superconductivity at room temperature. The paper in arxiv aroused doubts in the scientific world, but nothing was said after that.
However, the team has reviewed the paper to a new...
I've set up a simple experiment to look at the ideal gas laws. My experiment is relatively simple in that I have a metal tube which is capped on one side. I am then pressurising the tube with air to 100 psi and locking it off.
My thought is that as the pressure increased, with volume held...
In my quest to understanding radiation of the electromagnetic spectrum and the things around me I would like to confirm if I understand this correctly...
- The color of objects around us doesn't always mean they are hotter than another just because of the color it has, for example: A blue...
In a drinking bird, water from the wet on the outside of the head evaporates, causing the vapor inside the head of the bird to cool. This reduces the pressure of the vapor at the top, allowing the higher pressure in the lower bulb to push up the column of liquid.
But the bird's body (including...
I have a couple of questions related to this task.
The reaction that I proposed was this:
NaOH(aq) + HCl(aq) <--> Na+ + Cl- + H2O (l)
where as the solution manual have this net reaction, as nothing will happen with the Na+ and Cl- ions:
H+ + OH- <--> H2O.
I assume these reactions will...
I have a heat & mass balance diagram wherein there is a shell and tube heat exchanger to recover heat from hot exhaust gas using cold water. The exhaust gas inlet temperature is 120°C and the outlet is at 40°C. The inlet water temperature is 35°C while the outlet water temperature is at 50°C...
Summary: 1.In the context of calibrating a scale to correlate volume change with temperature, my book states: "Since all substances change dimensions with temperature, an absolute reference for expansion is not available." What do they mean by an absolute reference in this instance?
My...
I have a problem that i cannot solve despite my best efforts. I do realize not all information here is relevant, but i still included it so you could get the full picture.
Imagining we have a cylinder that is filled with dry air (normal air without water vapor) that has a fixed volume of 8,5...
mass of N2 = 28 * 1.67e-27 kg
not sure if this is the right one - just googled it
triple covalent bond N2 radii = 54e-12 m
I tried to first find the rms speed:
v = x/t
= 50 * 54e-12 / 3 m/s
Then I solved for T (in K):
[50 * 54e-12 / 3]^2 * [28 * 1.67e-27] / [3 * 1.38e-23] = 9.14e-22 K
This is the final question on my assignment and I'm clueless as to where I should even start as the lesson seems to give no guidance. Help would be massively appreciated!
For a throttling valve C.V analysis, I am wondering why is it known that temperature remains the same for ideal gases. I understand that using the energy balance equation, I end up with h1=h2. Pretty simple so far. By breaking down enthalpy into its components u1+P1v1 = u2+P2v2 I realized that...
Hello,
My sources seem to contradict here - one claims that it should be carried out at room temperature, while the other suggests that heating under reflux is necessary.
Could someone please clarify this for me?
Many thanks.
This quote from Wikipedia says that temperatures in the Thermosphere can reach 2,500 C during the daytime but "despite the high temperature, an observer or object will experience cold temperatures".
"The highly diluted gas in this layer can reach 2,500 °C (4,530 °F) during the day. Despite the...
Hi, I'm reading Lamarsh's book "Introduction to nuclear reactor theory" and in chapter 7 he discusses the influence of temperature on the resonance escape probability. He states that after an increase in Temperature, as a consequence of Doppler broadening, the microscopic absorption cross...
If I had an object in an orbit around the Earth that I kept continually shaded from the sun, how cold would it get?
Assuming the shade device was not physically connected to and was sufficiently far away from the object to not radiate any heat to it.
And if I actively adjusted how much shade...
Please below attached which is best oil in my 4 stroke gen set Honda EU 10i, weather temperature attached in my area. I all so have two oil grades > 4T 10w-30 and Coastal Synthetic Blend 5W-30, please advice which will help the life of the gen set
P_b/P_a =0.4
I have calculated mass of the syrup which is 0.42g
We know that the power of a laser before is 100mW and after is 40mW, that means that the energy absorbed by the syrup is equal to 0.6J/s.
I'm not really sure what to do here, the substance through which laser is going is Maple...
We are told that temperature measures the average kinetic energy of the molecules or atoms in a substance, but this cannot be true.
If I take a jar of water and put the jar in my car and drive it aorund, it won't get hotter, though it's kinetic energy must surely be higher.
Clearly, I've got...
This seems like a simple thermodynamics question but I would like clarification. So the absolute critical temperature is 132.5 K (-221.17 F) and the absolute critical pressure is 3.77Mpa (546.7 psi). I understand that for temperatures above the critical point, a pure substance undergoes an...
Hi PF! I have a tricky problem that I'm trying to model, and none of the typical textbook examples cover this--or they only cover it tangentially--so I was hoping to get some insight here. (Couldn't find a "Thermodynamics" section of the forums so if there's a better place to post this, please...
Is there any material/s that will handle CVI furnace temperatures (1250 C) and will either repel carbon deposits or react with it to create a compound that is not electric conductive? Trying to contain power to the heating element without shorting it to the base/ground through heating element...
Does temperature increase when water is boiling at 100C in a closed system? I am picturing a scenario where I am boiling water in a pot to make pasta. However, I decide to close the pot as the water is still boiling. By doing this I am sealing away the system of study from the environment. Thus...
1. The problem statement, all variables and given/know
Given: Nitrogen: 2g, it takes 820cm3 at 2 atm pressure. What is the temperature (T) of gas? Answer: 280K
Homework Equations
P*V = n*R*T
P - pressure
V - velocity
n - moles?
R - constant, 0.0820 ? when I use liters, atm
T - temperature in...
Homework Statement
Imagine two parallel plates at distance ##L##. One of them at constant temperature ##T_H## and the other one at ##T_C##. Media between the plates is air.
Find ##T## as function of distance from the plate with ##T_H## in steady state.
Homework Equations
Navier - Stokes
Heat...
Does temperature apply to subatomic particles, in particular the neutron? The question is prompted by the definition of absolute zero, being specific to atomic movement.
Greetings,
I read with interest some of the reports and studies of the "measurement" of the temperature of interstellar gases(H2, O2 etc) surrounding some gaseous nebulas(nebulae). Some reported temps. are in the thousands of degs. K. I was wondering how a solid object traveling at high speed...
Hi,
In the Stefan-Boltzmann equation for radiation heat transfer, there exists expected parameters of any model (area, constants, etc.). However, the temperature is raised to the fourth power.
Can someone explain why?
I get that it could just be because it has been "experimentally observed."...
Hi,
I want to develop a Monte Carlo simulation to determine the temperature of a beta radioisotope (Sr-90) of a given mass for my master thesis in Computational Physics. I am rookie to simulations. How much time will take to develop such a code.
Thnaks a lot
Given that absolute zero is the lowest temperature possible, were all particles have zero vibration. And given that the speed of light is the highest speed any object, particle, sub atomic or not can travel. Using 2 of the most fundamental laws of physics thermodynamics and general relativity...
How can I calculate the surface temperature of a Cylindrical Heating rod after some time interval? There is internal heat generation in the rod and convective heat transfer to the surroundings.
Hey, I'm interested in temperature recordings for the last 10 years but also for an estimate in the last billion years, this for hobby and fun. There are a lot of public sources but problem is many sites are torn down and others are created, so I feel very in the wild, it's like finding a tree...
I thought this would be easy to find - but I can't find it. All the data I can find on-line is local to location.
I am looking for data showing the highest recorded temperature on the planet per year over the past 30 years.
Does anyone know if such data is compiled / accessible?
Homework Statement
[/B]
Find the equation of state of a solid that has an isobaric expansion coefficient
dV/dT = 2cT - bp
and an isothermal pressure-volume coefficient
dV/dp = -bT
(Assume the solid has a volume Vo at zero temperature and pressure. Enter a mathematical equation. Use any variable...
I've been logging daily temperature and humidity data for two years now. In the end of each year I will put a graph like this
Those are daily minimum and maximum temperatures. But I was wondering, if all this has any scientific value at all. I've been using WS2300 weather station for these...
Homework Statement
A brass bar and a steel bar, each 0.8 m long are at a temperature of 20oC. Each bar is placed at that temperature between rigid walls 0.8 m apart. The cross - sectional areas for the brass and steel bars are 0.005 m2 and 0.003 m2, respectively. The coefficient of linear...
Homework Statement
An insulated beaker with negligible mass contains a mass of 0.350 kg of water at a temperature of 76.5 °C.
How many kilograms of ice at a temperature of − 23.9 ∘C must be dropped in the water to make the final temperature of the system 40.0 ∘C?
Take the specific heat for...
So we have that KE= (2/3)kT , meaning that if I increase the kinetic energy of water, it will become hotter, I searched it and it says that at the bottom of the waterfall, the water is slightly hotter. Of course I imagine that when they refer to the bottom, they refer to a part of the waterfall...
Earth rotates, it also orbits the Sun, the Sun orbits the galaxies and these have they’re own velocities as well. We know that the kinetic energy is measured by its velocity, and also that kinetic energy is related with temperature. By this I mean that the movement of particles are a measure of...
For ##m>T## we can write
$$n\propto T^{3/2}\exp[{-(m-\mu)/T}].\tag{2}$$
For ##T>m## we can write ##n\propto T^{3}## where ##n## is number density of particles with mass m. We can derive this relationship by using ##n\propto a^{-3}## and we also know that ##a\propto T^{-1}##.
Is there a...
Hi guys,
I'm having an issue at the minute with rolled coil steel, cracking and fracturing when being rolled into a profile. The material certs are within ISO specification, i.e. chemical composition analysis and the mechanical properties etc.
The carbon equivalent may be a little high, but...
Homework Statement
A system consists of a mass m moving in one dimension and attached to a rigid wall by a spring having stiffness constant ##K##, as shown. The mass is subjected to a constant force ##F##, and is in equilibrium with the surroundings at a temperature ##T##. The partition...
In my assignment question, the length L and radius r is given and asked to find out how the Temperature of a thin bulb filament which depends on those two parameters. and the answer is r^(1/4)*L^(-1/2). I can't figure out how. Which relation is involved?
Good day all!
I have the following exercise
One kilo-mole of air expands adiabatically from an initial state p1=1 bar, T1=340 K to a final state V2= 2V1. Compute the temperature of the final state, for the following cases: Joule expansion (gas free expansion with W12=0)
My problem is with the...
I am interested in whether it may be possible to reduce the temperature of the Hall-Héroult process for the electrolytic smelting of aluminum by using Li3AlF6 instead of cryolite (Na3AlF6) as the solvent for the aluminum oxide, and if this might be advantageous over current methods.
Li3AlF6...