Capacity Definition and 639 Threads

The heat capacity equation Cp for copper as a function of temperature (Shomate equation) for the solid phase is defined for the range of 298-1358 K in the Nist Webbook and in many books. http://webbook.nist.gov/cgi/inchi?ID=C7440508&Mask=2#Thermo-Condensed And I need to calculate the heat...

A 2.5 inch diameter disk plate has 6 plates , 512 bytes per sector , 256 sectors , 5268 tracks per surface. What is the capacity of the disk in terms of Giga bytes ? In the solution of my book ..written: 6 plates = 6x2-2 = 10 recording surfaces // I don't understand this part. Could you...

Morning I am being stupid but cannot work out these problems: 1. Energy supplied to 2.0 moles of an ideal gas is 117J and it changes the temperature by 2.0K (at constant pressure).2. Calculate both molar heat capacities at constant P and V.3. Firstly, I divided 117J by 4 to get the energy...

Hi everyone, I am new here... please forgive me if my posting is imperfect :p I am planning to purchase a glass aquarium with tank dimensions: 48" (Length) * 24" (Depth) * 22" (Height) I wonder if a wooden stand with only edge support will be able to withstand the weight of the filled...

Hello all, I am taking a thermodynamics course and unfortunately my professor is not very instructive. I have attended every class and I still feel lost. I was wondering how it is possible to find heat capacity if both the pressure and the volume are changing? I was under the impression that...

According to Einstein (or Debay) model of solids, heat capacity drops exponentially at low temperatures: question is >> why it changes so dramatically at low temperature that is physical explanation of this?

Hi guis, i need your help... 1. Homework Statement Evaluate the rotational and vibrational contributions to the heat capacity of a gas of DBr (D=deuterium, Br=mixture at 50% of 79Br and 81Br) at 380 K temperature, knowing that the bond distance is 1.41 Å and the vibration frequency of 1H79Br...

Homework Statement I have ##C= NK_B (\frac{\epsilon}{K_B T})^{2}e^{\frac{\epsilon}{K_B T}}\frac{1}{(e^{\frac{\epsilon}{K_BT}}+1)^2} ## and need to sketch ##C## vs. ##T## Homework Equations See above The Attempt at a Solution I have ##C= NK_B (\frac{\epsilon}{K_B...

Homework Statement In an industrial fryer is f.e. 400 kW. Heating capacity installed. The fryer may contain as much as 1.450 ltr of oil. I can fry 2.000 kg of chicken nuggets per hour in that. These products loose 7% of moisture/water in this process. That water can only escape from oil in gas...

Homework Statement Body X whose temperature is 0 °C is brought into thermal contact with body Y of equal mass and temperature 100 °C. The only exchanges of heat that take place are between X and Y. The specific heat capacity of X is greater than that of Y. Which statement about the final...

First off, I am new to this forum.. However I wanted To find out if anyone would be able to help me calculate How much a steel bar (2 in. In diameter, 5 ft. Lengthwise) Would be able to hold up without bending?

Homework Statement A cylindrical metal can is to be manufactured from a fixed amount of sheet metal. Use the method of Lagrange multipliers to determine the ratio between the dimensions of the can with the largest capacity. Homework EquationsThe Attempt at a Solution $$V(r,h)=\pi r^2h$$ $$2...

Homework Statement Hi, I have an assignment to determine the specific heat capacity of water using a calorimeter, voltmeter and ammeter, where we connected the calorimeter to a 10V power pack and measured the temp of the water and the readings on the voltmeter and ammeter every minute. I ended...

Homework Statement A 75.0g ice cube at 0 C is placed in 825g of water at 25 C. Find final temp. Homework Equations Well none really, this should be simple plugging into to heat equations. The Attempt at a Solution Heat required to melt ice = (0.075kg)(3.33*10^5) = 24975 J Heat required to...

Homework Statement A metal block of heat capacity 60 J K -1 loses 1MJ of heat energy to its surroundings. Find the decrease in its temperature. Homework Equations Q = m c Δ θ Heat energy added = mass x specific heat capacity x rise in temperature heat energy lost = blah blah blah x drop in...

I started simply looking at a circuit breaker connection diagram, then I fell down the rabbit hole. So I wondered, if you had a piece of pure copper and getting rid of heat (structural integrity, gravity etc.) was not an issue, just how much current could you push through it before it hit it's...

Hi, I am a university student in the Netherlands and I just got the assignment of building a robot on a budget. Because of this budget I would like to make the battery pack that powers the 2 servo motors and 2 electric motors myself. I did some research and found out it would be best to...

HOMEWORK POSTED IN WRONG FORUM, SO NO TEMPLATE I have encountered a problem at the university in which there is a thermally isolated container of constant volume in which the number of particles and temperature change with time(the temperature increases). The change in particle number ensures...

Hi guys! For a school experiment we are supposed to connect a 9v battery to a 180 ohm resistor and multimeter and calculate how long it take to die at different temperatures . does anyone know how can i do this using a formula? I will need it in my report. Thanks for the help! :)

Svein submitted a new PF Insights post An Analysis of Road Capacity Continue reading the Original PF Insights Post.

hi am planning to buy a electromechanical relay with following specification: 16A 256VAC 60HZ, 3PDT this relay is used for controlling a heater. heater's specs are 2000W 256VAC I have found one matching for this spec from TE.. its specs are 16A 256VAC switching capacity: 6000VA what does...

Homework Statement Silver has a Fermi energy of 5.48 eV. Calculate the electron contribution to the molar heat capacity at constant volume, Cv, of Silver at 300 K. Express your result as a multiple of R. Is the value of Cv due principally to the electrons? If not, to what is it due? ans...

Hello. I am doing a research paper on the relationship of specific heat capacity and refractive index of liquids. I am doing this by finding the relationship between specific heat capacity and concentration and refractive index and concentration. With this I can find a general trend and conclude...

Few days ago I got sample of toroidal core from my friend. Technical details of core OD-10cm, ID-6cm, height- 5cm and wet about 1.845 kg(M4 grade CRGO). I want to make toroidal transformer using this core but how to calculate core area and maximum VA capacity of core. attach Test certificate of...

so for one of my assignments i need to make a calculation which involves the mixture to be made of different types of substance... the heat capacity for each of the different unknown substances that were given: substance 1 = 1250J/kg °C substance 2 = 1130J/kg °C substance 3= 4100J/kg °C i need...

The door is 4.5 lbs evenly distributed. Width is 7" and length is 19". The door is mounted by using a friction hinge at the center . How to calculate the total load acting on the hinge? What is the maximum load bearing capacity of the hinge? Length of hinge is 3.2" and diameter of pin is .230...

I have been asked to provide an estimate of the maximum load capacity of a shelf that would be 4.5ft by 1ft The information I know is as follows: Bending Stiffness=1750 Nm Area of shelf= 4.5ft by 1ft= 4.5 ft^2=0.41806368m^2 Thickness of shelf= 18mm I need either the equations I could use to...

Homework Statement A 10.0 g sample of solid platinum is placed in a large, sealed vessel at a sufficiently low pressure that the platinum is able to sublimate directly to a gas. Some thermodynamic properties of platinum at low pressure are given in the following table. Molar mass, M - 195...

I have a simulation with a bunch of particles with volume bouncing around in a box with no interaction between them, a hard-sphere gas. Initially, they all have the same momentum |p|=√(2⋅m⋅2/3⋅k⋅T) to have the average kinetic energy 3/2⋅k⋅T. I'm asked to add a constant energy flux to the system...

As some of you might know, one of my hobbies is lifting stones. Besides regular weightlifting I do strongman things too. I need a book bag (or something I can put on my back like a hikers/adventurers/Indiana Jones bag) that can hold about 200lbs of "stuff", more would be even better. Right now I...

I am wondering if equation $$C_v=(\frac{∂U}{∂V})_T$$ applies only to ideal gases or applies generally for any other system? The second question I have is can we use the following relation: $$dU=nC_vdT$$ in processes that are non isochoric (that is for processes where volume is not constant)? I...

Hi, I'd like to know how I'd put together, either elegantly or at least in physical terms, that surely water evaporation in a large pool of V volume and S surface is influenced by wind (increased by it as opposed to having side barriers), temperature (increased by direct sunlight as opposed to...

Homework Statement A system of N distinguishable particles, each with two energy levels. The lower energy level has energy equal to zero, and the higher energy level has energy ##\epsilon##. The higher energy level is four fold degenerate. Calculate the heat capacity. Homework EquationsThe...

What is the heat capacity values of diesel in liquid and vapour state?

Homework Statement My answer is question 3 part c the graph. SHC = c http://www.ocr.org.uk/Images/61757-question-paper-unit-g484-the-Newtonian-world.pdf [See page 7]Homework Equations E=mcdelta theta Power=Energy/Time Therfroe Power*Time = Mass*c*delta theta. The Attempt at a Solution See in...

Homework Statement The specific heat capacity of a metal at low temperature (T) is given as ##C_p = 32\left({\dfrac{T}{400}}\right)^3## (kJK-1kg-1). A 100g vessel of this metal is to be cooled from 20 K to 4 K by a special refrigerator operating at room temperature (27°C). The amount of work...

Hi, Say we have fluid A with thermal capacity C_a and fluid B with C_b. If we create a solution with X% of fluid A and (1-X)% of fluid B, is it true that the new thermal capacity of the mixture will be C_new ?= C_a*X + C_b * (1-X) Or it is a case-by-case relationship that depends on the nature...

How does the current carrying capacity depends on the thickness of insulation of conductor ?

I believe my attempt below is correct but I'm not 100% sure, any guidance welcome. 1. Homework Statement Suppose a meteor of volume 1000 km3, density 5000 kg m-3 and speed 30000 km hr-1 crashed into the ocean and 10% of the impact energy was converted directly into heat. i) Estimate the...

Homework Statement The graph below shows the result of an investigation in which an initially solid specimen of nitrogen absorbs heat a constant rate. Nitrogen melts at 63 K and the specific heat capacity of solid nitrogen is 1.6 kJ kg^-1 K^-1. Homework Equations shc od solid nitrogen = 1.6...

Generally in chemistry and physics, we learned that a material has a heat capacity at constant pressure. However, I am confused at whether this refers to a constant external pressure or a constant system internal pressure? Thanks.

Hi friends , today we are just general talking with my boss. and he asked me a question . and that is, if we have equipment that is rated short circuit current is 40kA. for 1 sec. and if we must have to use that same equipment for 3 sec time. that how much short circuit current they can...

Homework Statement If a metal is highly susceptible to oxidation, what effect might this have on calculating the quantity of heat transferred to a metal? Use specific examples. Homework Equations Q=mcΔT The Attempt at a Solution Would oxidation change the specific heat of the metal? Since...

Equations: E=m*c* dTheta or T Experiment: I had two beakers of water with one thermometer in each beaker. One beaker had boiling water and the other beaker had room temperature water. I also had a 100g mass. I recorded T1 which was the intial temperature of the cold water. I then put the mass...

hi guys... am working on a variable refrigerant flow (VRF) type air conditioner. my aim is to change the capacity of the compressor based on load change. i can vary compressor capacity by using inverter...now my doubt is on what basis i should change compressor speed for muti evaporator...

Let's say that we have some canonical ensemble where I know that the heat capacity is given by ##C_{V}=\alpha(N,V) T^{n}## Since ##C_{V}=T\frac{\partial S(T,V)}{\partial T}## I know that ##S(V,T)=\frac{1}{n} \alpha(N,V) T^{n} + f(N,V) ## Where the function ##f(N,V)## has to do with the fact...

I have always had a fascination with trying to come up with new and unique, and (possibly) practical ways to increase the warm weather output capacity of combustion turbines. Any help or suggestions for possible options would be appreciated. In warm weather the density of the ambient air drops...

Homework Statement Initially we had a circuit with 2 transistor , we draw the equivalent circuit in the dynamic range and low frequency . After that we simplified the Circuit by calculatuig Rin after the capacity . So what we have left is a voltage source (ac) followed by a resistor followed...

Some articles would state that graphene(1 pure sheet) can carry x1000 the amount of current copper can. When I researched it, there isn't anything indicating so. Are those articles true? Or is it a lie? I understand how graphene can be slightly better, but that is unrealistic... it is a...

What is the correct notation for Volumetric Heat Capacity? I see it written both ways (Wiki for example). I'm pretty sure one is more correct but which is it? (1) Btu/ft³·°F or (2) Btu/(ft³·°F)