Capacity Definition and 664 Threads

  1. Rizwan Yaseen

    How to Convert Heat Capacity Equation Units to British Engineering System?

    How we change the units of Heat capacity equation to British engineering system Cp=2. 657*10^4 +42. 37T - 1. 425*10^-2T^2
  2. Carlos

    Heat capacity as a function of T under 298 K for metals

    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...
  3. M

    How to calculate the capacity of a disk

    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...
  4. N

    Molar heat capacity at constant pressure/volume

    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...
  5. Togmeny

    Help with calculating tank weight wooden stand can handle

    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...
  6. gsyz

    How can heat capacity be determined when both pressure and volume are changing?

    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...
  7. pangru

    I Why does the heat capacity of solids drop exponentially at low temperatures?

    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?
  8. B

    [PoM] Rotational and vibrational heat capacity

    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...
  9. binbagsss

    Plot Heat Capacity vs Temperature for a 2 state system microcananonical ensemble

    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...
  10. Adrianus

    What heat capacity is needed to evaporate water in oil

    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...
  11. T

    Thermal Physics (Specific Heat Capacity)

    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...
  12. E

    Calculating steel round bar's max capacity to support?

    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?
  13. toforfiltum

    Find ratio between dimensions of can w/ largest capacity

    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...
  14. VegemiteJuice

    Determining the specific heat capacity of water

    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...
  15. S

    Heat Capacity and Latent Heat question

    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...
  16. RabbitWho

    Find the mass of a metal block with heat capacity 60JK

    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...
  17. T

    Maximum current carrying capacity (theoretically infinite?)

    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...
  18. CasVS

    Electrical Maximizing DIY Battery Pack Capacity: Understanding Amp-hours vs. Watt-hours

    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...
  19. J

    Heat capacity under constant pressure or volume question

    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...
  20. A

    How Can I Calculate Battery Discharge Time Using a Formula?

    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! :)
  21. Svein

    Insights An Analysis of Road Capacity - Comments

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

    Understanding Relay Ratings for Controlling Motors: A Comprehensive Guide

    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...
  23. K

    Calculating molar heat capacity from electron contribution

    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...
  24. J

    Specific heat capacity and concentration

    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...
  25. SanPhysics

    How to calculate Toroidal Core Maximum VA capacity

    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...
  26. timelesstrix0

    Specific heat capacity of a mixture

    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...
  27. R

    Load bearing capacity of a friction hinge?

    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...
  28. Q

    Finding the maximum load capacity of a shelf

    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...
  29. S

    Thermodynamics and heat capacity

    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...
  30. adriplay

    How to Determine Heat Capacity in a Hard-Sphere Gas Simulation?

    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...
  31. OrangeDog

    Need a Book Bag That Can Handle 200lbs? Any Suggestions?

    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...
  32. M

    Heat capacity at constant volume and internal energy

    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...
  33. Alfreds9

    Water evaporation, temperature, wind and heat capacity?

    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...
  34. B

    Heat Capacity of Distinguishable Particles

    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...
  35. Y

    Specific Heat Capacity Graph Question

    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...
  36. E

    Specific heat capacity of a metal at low temperature

    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...
  37. P

    Does Mixing Fluids A and B Create a Predictable Thermal Capacity?

    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...
  38. A

    How does the current carrying capacity depends on thickness

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

    Meteor impact - Heat vaporization and capacity

    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...
  40. H

    How Do You Calculate the Specific Latent Heat of Fusion of Nitrogen?

    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...
  41. F

    What is meant by heat capacity at constant pressure?

    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.
  42. K

    Weird questions about short circuit current capacity

    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...
  43. Marcin H

    Oxidation and specific heat capacity

    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...
  44. Reety

    Why do lower temperatures result in lower specific heat capacity?

    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...
  45. srinaath

    Air conditioner compressor capacity control in VRF systems

    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...
  46. Coffee_

    Finding the entropy from the heat capacity

    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...
  47. M

    Combustion Turbine Capacity Enhancement?

    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...
  48. P

    Capacity with 2 R in RC circuit

    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...
  49. PhiowPhi

    Is Graphene's Current Capacity Really x1000 Times Higher Than Copper?

    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...
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