A central heating system provides warmth to the number of spaces within a building and optionally also able to heat domestic hot water from one main source of heat unlike heating, ventilation, and air conditioning system which can both cool and warm interior spaces.
I need to work out the most cost effective way to maintain a swimming pool in a UK holiday complex that is closing for 1 month in January and hope that someone can help.
I would like to know if it would be cheaper to turn off the heating system for a month and then reheat it from base...
Hello!
I have some troubles finding a way to estimate how much temperature of liquid would rise when it is suddenly adiabatically pressurized to thousands of bars. In normal conditions liduids such as water are considered to be incompressible, but certainly not in 5000 bars. Because water (or...
Once during a severe hail storm (it lasted a few minutes and looked like it had snowed everywhere),
my friend starting jumping around as if something was burning him, and he pulled 2 AA batteries out of his pocket and threw them outside. They were really hot and quickly melted a hole in the...
I was wondering if somebody could explain to me how does the process of Enceladus being heated up satisfy the laws of thermodynamics, more precisely the conservation of energy.
Or should I ask where is the payment for the giant geysers on that moon? In layman terms, please!
If I tightly packed oily sand in my microwave and turned it on would it heat the sand and oil? If paraffin and salt water were present would it heat everything? Could I send the microwaves to the oven from 1 mile away thru a piece of metal conduit?
How long would it take to boil 1.5 litres of water to achieve 55c if the temperature heating up the water was 55c?
The starting temperature of the hot water being heated would be 50c.
Wikipedia has this to say about joule heating:
"Joule heating is caused by interactions between the moving particles that form the current (usually, but not always, electrons) and the atomic ions that make up the body of the conductor. Charged particles in an electric circuit are accelerated...
Hello,
Stupid computer scientist student speaking here.
I am looking to heat a few inch long glass tube with a OD of around 10mm and wall around 1.5mm wrapped in Nichrome wire to around 365F. Air will then be drawn through the tube to heat up herbs sitting about the glass tube. (vaporizer) I...
Hi all. I'm trying to find haw much energy is required to get the air heated up to one desire temperature in oven. . I guess the next issue will be haw much energy is required to keep the temperature at the setting point.
A theoretic starting point will be useful from your side, if possible...
i have decided to heat pipe using wounding SWG 26 nichrome wire around the pipe,can anyone suggest me a good insulating bead which conducts heat well but is a good current insulator
Good Day, I am looking for mathematical modelling of Joule heating of a simple cantilever beam . Can anybody provide me good source of relevant material.
Thanks in advance.
This is just a qualitative question but feel free to show an equation if possible.
Basically if you have a container with a heating element, let's say 500 W with a temperature of 2500 Kelvins and inside this box is a low pressure ideal gas, something like 1/100 of an atmosphere. Also imagine...
Homework Statement
1kg of silver is heated by a large heat reservoir at 373 K from 273K. Calculate the change of entropy in:
a) the silver
b) the reservoir
c) the universe.
Homework Equations
ΔS = ∫dQ/T
The Attempt at a Solution
calculating the change in the silver first
ΔS = ∫dQ/T...
Homework Statement
I am confused about the heating of the unstable complex:
##[Fe(H_2O)_5(NO)]SO_4##
In one place I read that it gives ##FeSO_4## , whereas in other place it says ##Fe_2(SO_4)_3##.
So which one is correct?
Homework EquationsThe Attempt at a Solution
I really don't have any clue...
Ok I have a question that hopefully someone can answer. I'm an electrician and I recently had a service call where a hotel had a 175 amp 3 phase breaker feeding an ac unit with 4 compressors and 2 blowers that kept tripping. I first checked all the compressors and blowers to see if they were...
Ok, first off I need to explain my project first.
I have a wood pellet stove that I want to use to heat hot water for a radiant heating system. I will have to do a custom job because nobody makes a kit for my particular stove.
My question is howong of a colper tube is needed to heat the well...
Homework Statement
A ring of radius R is kept in the xy plane and a constant uniform magnetic field exists of magnitude B in the -k direction (negative z direction ) . It is heated through a temperature T . If the resistance of the ring is R1find the final radius of the ring. Coefficient of...
Hi,
I am doing an experiment on the factors affecting the time to heat water from a set temperature to another, eg 20 to 35 deg C.
1. First, I have insulated the beaker properly, to minimise heat loss. I have connected a heating element to heat the water. Connected multimeter, give the voltage...
1. I'm trying to work out how much energy is used in heating 2 cubic metres of water per day from 23C to 65C. Basically trying to put a water purifier in Malawi and run it off solar panels. It currently uses 1.3kWh to run the machine but the initial stage involves pre heating water. In Malawi...
Homework Statement
The temperature variation at the surface is described by a Fourier
series
\theta(t)=\sum^\infty_{n=-\infty}\theta_n e^{2\pi i n t /T}
find an expression for the complex Fourier
series of the temperature at depth d below the surface
Homework Equations
Solution of the...
hello,If anyone of you help me in finding specification(diameter of nichrome wire required) for a 2 m nichrome wire to heat up to 65 degree Celsius .Voltage applied is 12 v. I want to use it by coiling it to cylindrical mica sheet to make a smaller heating product.Temperature should not exceed 65.
What is the solution of heat transfer equation when there is continuous heating ( flux of energy) to one end of a metal rod? what will be the temperature profile before reaching the steady state? when I try the boundary condition where one end (x=0) is kept at T1, I got the general solution of...
I'm currently studying ion trap experiments, many papers suggest the cooling of trapped ions, and other papers say its a heating process. I know there's a difference as to what each refers but am unclear of the difference. I'll quote...
As I know, when a string of solar cells connected in series, if one of the cell is shaded, it will be reverse bias due to current mismatch and the voltage can be very high, say, 20V. But in short circuit condition, the overall voltage should be zero, if other cells are in forward bias, how can...
When you increase the resistance of a filament bulb more work is done on the bulb which means its temperature increases. This causes the ionic lattice to vibrate with a greater amplitude (since it has more kinetic energy). The conduction electrons now encounter more collisions, hence the...
Hello,
I have a cylindrical aluminium tube ( Diameter- 8cm, Length-15 cm, Thickness - 0.5cm ). It is insulated from bottom and open from above. I want to raise the temperature inside the tube maximum upto 300 degree celcius in a controlled fashion. I want to use electric coils to heat it. Can...
I saw on TV this morning how Thomas Drummond in 1829 created an intense light for use in a lighthouse in 1829, before electric lights. He heated calcium oxide with alcohol and oxygen to a very high temperature creating what is called limelight, later used in theatrical productions in the 19th...
I need create a math model to predict the temperature of a copper pipe with hot air flowing through based on the temperature of the air, properties of the air and copper, and the surface area of contact between the air and the pipe. The pipe will start cold but I will be looking to the...
I'm having trouble understanding why 1) Heating a solution more slowly would increase separation in a distillation and why 2) Lowering the pressure above the solution, i.e. with a vacuum, would decrease separation.
Distillation depends on you collecting one component before the second...
Homework Statement
What size FPC is needed to supply a family's domestic hot water needs in March in Denver, CO? Assume 80 gallons per day are needed (1gal=8.3 lb.) for the water and that the collector-heat exchanger system has an average efficiency of 40%. The collector tilt angle is equal to...
Dear all
I have 250g of Copper 250g of Tin and 250g of Sulfur.
Everything is in powdered form.
Heated up in closed container wit surrounding nitrogen flow to avoid contact with Oxygen.
Heating ramp is 3 hours to 1000K.
What reaction will be the leading reaction?
How to calculate how fast will...
In a thermally insulated container was a mixture of ice and water. Then we have put a immersion heater ( P=400W). We started measure time and at the end of every minute we writed down the heat od mixture. First two minutes the heat wasn't changing, at the end of third it raised about 2°C, at the...
Hi there. Is there any element, when exposed to saline, will cause the saline to heat up? More to the point, I would like to add something to a jar of saline and heat it up. Is that possible?
Thanks, ~J
Homework Statement
Consider an ideal gas with C_V=6.76 \frac{cal}{mol \cdot K}. Calculate \Delta H and \Delta U when ten moles of this gas are heated from 273.15 K to 373.15 K.
Homework Equations
\Delta H = \Delta U + P\Delta V
Q=n C_V \Delta T
The Attempt at a Solution
As I'm given the heat...
Homework Statement
200 liters of water are heated from 100 to 650C by burning coal gas. The heat loss in the chimney is 25%.
How many cubic meters of gas are needed
Homework Equations
Calories required: Q=mc\delta t
Burning heat of coal gas: 4320[Cal/m3]
The Attempt at a Solution
Net heat...
Which do you believe is the best choice for a low temperature RF heating susceptor, i.e. - greatest rise in temperature vs. field strength. I am aware that Graphite (expanded graphite foil) has excellent thermal conductance in plane and therefore makes for very even heating patterns over large...
I see a lot of information posted on the inefficiencies of heating water to steam with microwave energy. I was wondering if anybody has thoughts on super heating steam with microwave energy? For example, could you run steam through a turbine at 300 psi (417 degrees F), return steam at 100 psi...
Homework Statement
Consider water contained in a cylinder at 25C with a frictionless piston with some weights on it. Initially the pressure inside the piston is 100kPa and then the water is heated such that the water does 290kJ/kg of work on the piston. Find the final temperature of the...
During summer my swimming pool is 23° C and my loft air is 53° C. (73° F / 127° F)
The sun shines on the metal roof with 1x10^5 to 1x10^6 W and I hope to move 10.000 - 20.000 W to the pool.
To move the heat down by an external water circuit to the water/water heat exchanger by the pool...
Hello,
I am a high school student carrying out a physics experiment.
I created a short circuit in order to see how much heat different types of metals would release when a current is running through them (4.5 A). In my experiment, I tested three different types of metals: Brass, Stainless...
You typically hear of radiative heating as exciting an electron to a higher state in an atom or molecule, but heat energy is the excessive vibration of a molecule. How do you reconcile these two models? I've heard of something called radiationless de-excitation whereby the electron passes its...
Hi,
I want to measure the effect of oscillating magnetic fields on oxidative stress in erythrocytes.
I will use frequencies ranging from 0Hz (i.e DC) up to 1MHz the field strength will be 10uT.
But I am not sure if I can do this. Wouldn't the oscillating magnetic field heat up the sample...
Homework Statement
A pot on a stove burner contains 10kg of water and an unknown mass of ice at equilibrium at 0degC at time = 0min. During the first 50mins, the mixture remains at 0degC. From 50 to 60mins the temperature increases to 2degC. What is the initial mass of ice? Ignore the heat...
I am writing an intro physics problem about a flowing stream. I am going to assume that all of the gravitational potential energy eventually becomes thermal energy of the water. I haven't worked it yet, but I'm pretty sure the flow rate and g will both cancel out and give me a constant change...
Watch this video:
Permanent magnets moving relative to a stationary copper tube generate Eddy currents which result in Joule heating of the copper. Simple enough.
Let's change the problem to a rotor with 4 (circumferential) permanent magnets rotating inside a stationary (aluminum or...
Ok so as fare as I understand the equation for Joule heating in a material with a DC current is I^2*R.
I am trying to calculate for the heating of carbon fiber in an argon environment. Carbon fiber has a resistivity similar to graphite (roughly 5.0*10^-7) I am trying to calculate for 3.3VDc...
I am doing R&D and have been hit by a problem. I want to find the resonnce frequency to my heating coil without having to hook it up to the rest of my oven. I fall into the problem because I don't have the stray funds to buy a frequency generator. I heard that with capacitors and an oscilloscope...