What is Heating: Definition and 616 Discussions

Homework Statement This question is from a thermodynamics test from a previous science olympiad competition that I am using to study from for a future test. "Consider two neighboring rectangular houses built from the same materials. One of the houses has twice the length, width, and height...

I'm trying to make ferrofluid according to this guide: http://www.sci-spot.com/Chemistry/liqimag.htm and in step 5 I need to heat the solution to near boiling but I don't have access to a bunsen burner or heating plate. Also I can't do this in the kitchen because this heating is to remove...

I am idly curious about induction heating; specifically for heating 80L-100L of water from 20C to 100C as efficiently as possible with an emphasis on as little waste heat going to the surrounding environment as possible. I have done some precursory reading (...

Hi, I want to heat the FEL beamline for the outgassing process with an induction heater. What frequency should I use in the driver circuit of the heater? The geometry of the beam line as you can imagine is cylindrical. And do you have any experience about it? If its so, I will be...

Whenever I watch F1 motor racing there's always a lot of talk about how important it is to keep the tyres warm, why don't F1 tyres have heating elements built in so that the tyres can be kept at an optimal temperature all the time?

I have a question about efficiency of electrical heating vs. mechanical heating. Let me explain an example: I have two containers with 1 litre of water each. In one container I use a electric heater (electrical resistance) 1W. In the other container I use an electric motor attached to a...

Hi there! I recently noticed that the little drainage tube in the back of my fridge keeps blocking up with ice. As a result massive condensation develops around the ice which eventually drips down the back causing the bottom of the fridge to fill with water the whole time. Apparently the...

Hello everybody, hopefully I am posting this in the right spot. What I am trying to do is design a heating element powered by a Li-Po battery (RC battery probably) to heat a heating element to a range of 360-420°F. I want the temp to be adjustable, probably on three settings, so one for 360...

Homework Statement A portion of Nichrome wire of radius 2.50 mm is to be used in winding a heating coil. If the coil must draw a current of 9.25 A when a voltage of 120 V is applied across its ends, find (a) the required resistance of the coil and (b) the length of wire you must use to...

Homework Statement when heating i learned that only the kinetic energy component of internal energy increases. However, I also learned that potential energy is related to distance between the particles. So when i heat some solid and it expands does it mean the potential energy has changed as...

Hello, its my first post here, I had physics long time ago and now composing a system which need some (only probably) calculation. I have a water system containing 200 litres of water, its all in tube system which is vertically stacked, each tube have capacity of 10 litres, so there's 20...

I'm an engineer student and I'm trying to build such a solar heating system that it is drum with two layers, inner one is a metal (aluminium alloy I'm thinking) water container and outer layer is made of polymer, with air gap in-between. When suns come out, it radiates through the polymer and on...

I have to present an investigation on a topic that is related to healing and cooling. In class we're studying kinetic theory, ideal gas laws, heat, temperature, specific capacity, change of state, boiling and evaporation, energy conservation and degradation, and the transfer of heat. Are...

Aerocapture: Aerodynamics OR Aerodynamic Heating OR High-Altitude Atmospheric Model I apologize for the many topics covered at once here, but, this is why: I'm trying to design a vehicle to make aerocaptures from Earth to Mars, and from Mars to Earth (I do these kinds of things quiet a lot...

Hi. I'm trying to understand why smaller skin depths are better for induction heating. Skin effect means that the highest the frequency is, the thinest the skin depth is (or the depth is simply smaller because of the material). That means the section of the workpiece with electric current in...

Homework Statement There's a metallic rod of length l1 which is spinning around a vertical ax which passes through its center. The ends of the rod are spinning with ω1 angular speed. Homework Equations Determine the temperature at which to heat the metal rod so that the angular speed of...

Hi. Practical situation. If I have 0.25W of constant Joule loss around a small piece of copper electric conductor, then I would like to find out how much time until a small piece of "Something" (let's say 100mg at 1 kJ/kg*K) around the conductor heats up to 200°C. From my calculations...

Homework Statement ==================== <---- aluminium plate ⁣⁣⁣⁣⁣⁢⁢⁢⁠⁡⁡⁢⁢⁢...O .....O... <---- heat coil(O) Given an aluminium plate put on 2 heating coil(O), assuming no heat loss, how much is the heat transfer rate from the coil to the plate? Put the power of each coil as W...

Hi guys, Little stuck on the following thermodynamics question; A piston-cylinder contains 1kg of water at 100kPa in a 2-phase mixture (liquid and vapour). Heat is transferred to the water by a resisance heater The piston is free to move and the cylinder is insultated. The water is...

Hi I've come across a problem at work and was hoping someone could help me to understand what is going on exactly. power supply: 6kW, 9.2A, 5890V, and running at approx 50kHz. this power is routed through ∅3mm Kanthal AF bar, threaded at one end, and what we see is resistive heating...

I bought a cheaper set of roller blade wheels (you get what you pay for). With new wheels installed I had to work much harder to take longer on my usuall route. The new wheels had a hardness of 82a. The original wheels had a hardness of 80a and the last set had a hardness of 85a. The new wheels...

I'm trying to increase my understanding of what happens to waves with interference so I'll ask the following question to try and do so. If one had a pool of water with a wave machine pulling the side in and out all along one side and an identical wave machine on the other side working in...

I'm a little confused. Lets say i have a rigid,non-expandable container. If i heat the container,the gas molecules gain Kinetic energy. I initially learned that the gas molecules will hit the wall with a larger force,hence larger pressure.But F=MA,so the gas molecules are accelerating?But...

For example, if I had contained helium, and then I increased the temperature and installed spinners and motors inside would that move due to the activity produced by the high energy helium , or would the movement caused by the helium not be powerful enough to move the spinners. (I think it...

Homework Statement A composite rod is made if copper and wood joined together. a piece of paper is filled in close contact with both rods bear the junction of wood and copper. The rod is passed several times through a bunsen flame. What will be observed and why? A: the portion of the paper in...

Hi, I'll cut to the chase: I've been designing a project that uses a series of MCUs and such, in order to control a series of systems. The device is ment to run from a standard 120 V wall outlet, has a few motor controls, a piston control, but problematically also needs a heating element that...

I'm experimenting with induction heating, and made a simple ~100W device. Royer oscillator type, 200kHz frequency. It readily heats a steel blade to the point of incandescence. However, a piece of aluminium of a similar size doesn't even get warm. I understand that magnetic hysteresis...

When we deal with heat capacity or specific heat capacity Q=mc(delta temperature) why don't we take into consideration about the expansion of the thing? Since expansion (should) increase the potential energy of the item since potential energy is the bond strength which is related to the particle...

Homework Statement I am supposed to design a control system with feedback and disturbance feed-forward, with all relevant transfer functions. The system consists of an oven where the temperature T is controlled by an electric heater that dissipates power P_{in}. The temperature outside...

the hotter an object is, the bigger it is. So, what is happening with atoms? Do they get bigger or are they any further from themselves? I'm interested in it and as I think the bigger temperature they have the bigger are those nuclear or atomic forces so they are further from themselves. I also...

There is a spherical lead ball with a spherical cavity. It is heated. The size of the cavity increases. Why does it do so? Also, does it matter what happens to the cavity if it is not present at the centre, but rather a little removed from the centre? Will it remain spherical?

Gamma (Cp/Cv) of a gas Homework Statement An experimenter adds 980 J of heat to 1.75 mols of an ideal gas to heat it from 10.0 C to 25.0 C at constant pressure. The gas does 234 J of work during the expansion. Calculate gamma (Cp/Cv) for the gas. Homework Equations Cv=Cp-nR Gamma...

I was reading through my notes and this idea popped into my head: If you had to drop a liter of water from a certain height, could that potential energy before it's dropped be used to heat the water when it hits the ground? Like you got this equation ΔE = C ΔT Could one use that value of...

Ok, I know there is the argument about switching off/on a geyser versus the leaving it on all day argument, let's argue that for specific set of circumstance I have found out that the turn off method is saving me money. This choice now seems to have me in two minds. 1 is to keep the geyser on...

It seems that the recent developments in BWR fuels (increased enrichment, added uranium mass at the bottom, part-length fuel rods especially in the corners) have changed the control rod reactivity values in such a way that the potential reactivity insertion caused by the postulated rod drop...

hi guys.. I'm new here and this is my first post.. my friends told me that the title of this post is impossible and i need a car battery to heat the 800W nichrome wire, and i believe them.. they also said that AC will solve the problem.. but i need to use DC so i came up with using diodes.. the...

In order to determine the temperature that an electromagnet reached after a 3 minute period the electromagnet was placed in a constant volume of water. After 3 minutes the change in temperature of the water was measured and from this using the equation Q=mcΔT the energy in joules transferred...

I need to make a 1 metre long heating element from NiChrome Wire. The wire I have is 0.9mm with resistance of 1.7ohms per metre. Can I wire it straight to the mains with a light dimmer switch in place to limit the power?

Hello, I am a civil engineering student and I am currently taking a project design class that requires a bit of overlap into the mechanical field of thought. We have designed a 3-story108,339 sf. building that needs energy-efficient HVAC&R systems, among other things. Being a civil engineer, I...

I understand how the collisions between positive ions and electrons generate heat when a current runs through a wire. I, therefore understand that as temperature increases, collisions are more frequent, translating into a higher resistance. It then follows that, an increased resistance, due to...

I have a mountain cabin where 2 water pipes, hot an cold, goes between the bathroom and kitchen. However, they tend to freeze in the winter. The obvious solution is to put a heating wire along the pipes, but access is cumbersome. So I have thought about following solution: I ensure electrical...

How much power is needed to be able to melt aluminum using induction heating? So I have coil of copper wire around an aluminum cylinder. The aluminum is NOT touching the copper wire. the copper wire have a thickness of 0.5 cm. d = 0.5cm the copper wire is looped 20 times around. N = 20...

hi guys, m a lil stuck here what voltage would be rquired to heat a 7cm long copper wire of .75mm diameter in about 2-3 seconds.the target temp is 400-450c. dr ankit

The supervisor of my final year physics project has asked me to find the heating and annealing temp/times for PMMA (perspex) and Polypropylene. I've spent a good hour or so looking for them, but I'm not quite sure where to look. I'll be using the PMMA to make a variable-focus lens, and to form...

Homework Statement Hello, I am trying to simulate the heat diffusion from a laser beam striking a sample. My model/concept is very simple in that it assumes the temperature distribution will be a radially symetric sphere (i.e T=T(r,t)). I would like to plot a temperature profile evolving...

Hi the problem i am dealing with is that we want to heat samples up with a laser in our lab. For estimating the required laser power, as you know better than me, the main loss will be the heat diffusion in the material. My heat equation is in the following: \frac{du(x,y,z,t)}{dt} -...

Homework Statement To determine the Specific heat of an oil , an electrical heating coil is placed in a calorimeter with 380g of the oil at 10C. The coil consumes energy(and gives off heat) at the rate of 84W. After 3min the oil temperature is 40C. If the water equivalent of the calorimeter...

Hi all, Sorry if this seems trivial but I think I may have managed to confuse myself and could do with some help. I need to specify a tape heater power output for a small rig through which water will be heated to 200C. Having gone through the Q=m*cp*ΔT equation where: m = 0.1658x10-3...

What is the reason of Persistent Glowness of Platinum metal after removing it from the flame ?

hi, I need to expose metallic material in the WATER for a certain period of time (3, 6 and 12 months) at 100 °C (+/- 5 °C) and normal pressure. Is it possible to do that without using coolers? I was thinking of putting the glass vessels in the oven and closing it with some "special"...