Capacity Definition and 664 Threads

  1. M

    Deriving general specific heat capacity formula

    For this, Dose anybody please know of a better way to derive the formula without having ##c = \frac{\Delta Q}{m \Delta T}## then taking the limit of both sides at ##\Delta T## approaches zero? I thought ##\Delta Q## like ##\Delta W## was not physically meaningful since by definition ##Q## is...
  2. N

    Calculating Motor Load Capacity for a 4kg Vehicle

    TL;DR Summary: I need help with calculating how much a motor will be able to pull. Hi all, I am currently in my first year of engineering and we have a project which requires us to use motors to drive a 4kg max vehicle. I was planning on using the very common yellow DC motors which have...
  3. A

    How to obtain Axial Load Capacity from Tapered Roller Bearings Catalog

    Hello there, I'm trying to select a tapered roller bearing (TRB) for my actuator, I know the peak axial force that is going to come. I have some radial load as well. I want to select the TRB based on the axial load, but all the bearing catalogs or most of them give Dynamic and static Load...
  4. A

    Calculate Load carrying capacity of vertically mounted suction cup

    I'm looking for means of calculating load carrying capacity of a vertically mounted suction cup. Suction Cup effective diameter = 90mm Mounted on a vertical glass surface Pressure inside the suction cup = 0.75bar Pressure difference = 0.25bar Weight is suspended from a rod attached in the centre...
  5. Tone L

    Heat Transfer & Cooling Capacity

    Hi, zero education on heat transfer here, need some help. I have an electronics module that generates 15 W of electrical power over a 70mm x 20mm x 15mm heat load volume (aluminum). The ambient temperature is 25° C, the maximum temperature the heat sink can be is 40° C (ΔT = 15° C). Does...
  6. D

    Construction Steel cage weight load capacity needed

    I have a VERTICAL standing square tube 1.25" x 1.25" x 1/16" thick. Length/Height = 79" Material = steel How do you determine its max load capacity for this tube when mounted vertically? I plan to use 18 of these vertical posts, evenly spaced, creating an 83" x 131" rectangular structure. They...
  7. D

    Calculating Load Capacity of Steel Cage with A-frame Roof

    I have a steel cage 7 ft by 11 ft and 7 ft high. It's made out of standard 1 in square steel vertical tubing. Each vertical tube is spaced 18 inches apart all the way around the cage. All vertical posts are welded to a 2 in L-bar all the way around the top, and the bottom. I'm trying to...
  8. lxhull

    Specific Heat Capacity of a metal bar placed into water

    Previously solved thermal energy gained by water as Eth= 0.15(4180)(17.6) = 11035.2 J Not sure if its relevant
  9. Ahmed1029

    I Understanding Heat Capacity and Work: Clarifying Misconceptions

    In defining the heat capacity of a subatance as the constant relating change in temperature to change in heat, is it assumed that the system does no work? Does it really say (heat capacity is the constant relating heat change to temperature change when the system does no work)?
  10. L

    Tensile and shear capacity of metals

    Steel and other metals data sheets and mill specs most commonly quote some tensile strength metric, like Proof, Yield or Ultimate Tensile Stress. Less common is the value for shear strength. Often as rule of thumb the allowable shear stress is taken as half the allowable tensile stress but, when...
  11. A

    Fluid mechanics - Additional liquid capacity due to compression

    A cylindrical tube (diameter = D, width = L) is completely filled with a liquid (density = ρ). A pump pressurizes the system with a pressure P. Consequently, 1) the solid tube is compressed and deformed according to Hooke's law (σ = ε.E), and 2) the liquid is compressed and deformed, following...
  12. D

    Quantum computer storage capacity

    I have a question regarding the storage capacity of quantum computers. I read that 32 qubits (4 "quantum bytes" if you will - not sure if that's an actual term or not yet) can store the equivalent of 500mb of data. Is this directly proportional? I.e., would 8 qubits store the equivalent of...
  13. Wrichik Basu

    What is the correct way of measuring remaining battery capacity?

    I was searching for a way to measure the remaining charge of a battery using Arduino. Most (almost all) of the tutorials are simply measuring the battery voltage using the ADC on the Arduino. The calculations are pretty straightforward after that — ##5 V## is mapped to ##1023## and ##0## is...
  14. J

    I Calculating the specific heat capacity for the 2D Ising model

    So I'm looking at the book "Equilibrium Statistical physics" by Plischke and Bergersen. I'm doing the calculation of the specific heat of the 2D Ising model. I can't seen to quite get out the same expression as in the book - there are a coupe of minus signs that are different. I don't know if I...
  15. B

    Load bearing capacity of a tall column

    Could someone please tell me the load bearing capacity of an 8" x 8" x 10 foot tall white oak column. The oak is fully cured and would be placed on an appropriately sized concrete footing. It would be mechanically fastened to a beam that it would be supporting. Any assistance or explanation...
  16. Philip Koeck

    A Molar heat capacity of CO2 is too high. Why?

    At very high temperatures CO2 should have Cp = 15/2 R, since there are 3 translational, 2 rotational and 4 vibrational degrees of freedom. Experimental values are a bit higher than that, at least according to a figure I found on the internet. Is that correct? And what is the explanation? A...
  17. J

    I Impact, momentum, demand and capacity

    I'm struggling with trying to find how conceptually need demand and capacity to be conciliated during impact. In particular, I find two different formulas in papers and websites dealing with impact. In all cases, they state that there are two forces acting on objects on impact, where they...
  18. Grez

    Automotive How to calculate max car mass and tow capacity from motor specs?

    Hi I am trying to do an artisanal EV car and I would like to know how do I choose the right motor. I already have one in mind but I don't know how to calculate the max mass that it can move. (see attached pdf) Gear Ratio : 2.39 Diff Ratio : 4.88 Wheel Diameter: 26in I would like to know the...
  19. nemanjavuk

    Help understanding "Heat capacity"

    Homework Statement:: First of, this is not a "homework" per say, since this is not in my curriculum. If you still want to help, see the description :) Relevant Equations:: C = Q/(delta T), where delta T is the raise in temperature in Kelvin and Q is the added heat energy I want to learn about...
  20. N

    Why Is My Calculation of Heat Energy Incorrect?

    At first, I tried to calculate the heat energy required by doing this: I realized I should calculate heat energy separately instead of grouping glass and water together so I did this: But the answer is supposed to be 6.29 x 10^4. I don't know how to solve this. Can anyone help please? Thank you
  21. RalphZ

    Automotive Does vehicle weight have an effect on torque capacity of the gearbox?

    Hi, This has long been in my head, I've seen it work out in reality, but I have no idea about the forces involved in this. As I don't have an engineering degree or mathematical knowledge in automotive engineering, I've come here for help. Sorry if I've used some terms where they do not fit, as...
  22. C

    I Help please -- Trying to figure out rake barge capacity and displacement

    Barge size is 54.864 x 15.5448 x 2.95 m and Barge capacity 1500 ton Sorry to misunderstand. I am learning. Not to disturb others. My load is 350 Ton size above shown. What the draft after load the cargo on the barge? The barge draft 470mm Bow side after 5m has slope. I mean front side from the...
  23. StarChem

    Vaporization Heat and the Heat Capacity of H20 comparison

    According to the Vaporization Heat table, the heat needed for 1 mol of H2O to evaporate at 100°C is 40.7KJ and 44.0KJ/mol is needed to evaporate H2O at 25°C. Thus 44.0-40.7=3.7KJ is the energy needed to heat H2O to 100°C from 25°C. However, according to the heat capacity of H2O, 3.7KJ will only...
  24. G

    I Heat capacity for a real gas using the ideal gas (zero pressure) equation

    Summary:: Heat capacity for real gas with ideal gas (zero pressure) equation I'm looking at this problem and I'm stuck. I usually question everything but this problem is confusing me. I don't know how they've made the jump from reduced properties (from generalized Cp charts(?)) to...
  25. cwill53

    I Entropy and Heat Capacity Relation

    I have a simple question sort of about exact differentials and deciding which variables matter and when. I know we can write entropy ##S## as ##S(P,T)## and ##S(V,T)## to derive different relations between heat capacities ##C_V## and ##C_P##. I was wondering if it is technically correct to...
  26. M

    What's the load capacity of 6 aluminium posts?

    Hello First time here! I have acquired 6 aluminium boxes they are 2 metres in length, they are 150mm x 150mm square and the walls are 3mm thick (they are also powder coated). My plan is to use all 6 boxes upright as posts for a covered pergola or in other words a fancy BBQ hut, so I will be...
  27. T

    How to calculate the capacity of a disk drive

    Good morning, I got a question like this- "A hard drive has 6 platters, each platter records data on both sides. There are 3000 tracks of nine sectors each. Each sector stores 512 bytes of data. How many read/ write heads are there and what are the capacity of the drive(in Gigabytes)?" I...
  28. E

    A query about heat capacity and specific heat capacity

    Homework Statement:: why does heat capacity depend on the mass/size of the object when it's units is J/K , and why is specific heat capacity dependent on the material/substance when it's unit is J/kgK? Relevant Equations:: Q=Cθ Q=mcθ -
  29. E

    Specific heat capacity & heat capacity

    the answer is 1/2 , but when I did the working out, I got 2/1.. so I'm quite confused
  30. A

    Calculating specific heat capacity from entropy

    Hey guys! I'm currently struggling with a specific thermodynamics problem. I'm given the entropy of a system (where ##A## is a constant with fitting physical units): $$S(U,V,N)=A(UVN)^{1/3}$$I'm asked to calculate the specific heat capacity at constant pressure ##C_p## and at constant volume...
  31. J

    Find rate of temperature change using heat capacity, density and area

    So first I found rate of heat change using the above equation, with T=883K, e=1, SA= 6*l^2=21.66 Now dQ/dt=746593.71 W Now I am not sure entirely what to do next. They give density so I likely have to get the mass from that, M=pV,=1.9^3*4037=27689.783 kg. My issue is that I don't know how to...
  32. expn

    Exploring the Variation in Movement Capacity of Individuals

    Hello to all forum members, I came here in an attempt to find a solution to a problem that has been "haunting" me for some years. I have been trying for some time to understand mathematically the variation in the movement capacity of individuals, based on their effort. In other words, I would...
  33. C

    Current Capacity of short AWG 4 wire

    An AWG 4 wire has rating of 85A for 75C temp. If there was only 1 foot of AWG 4 connecting the bus bar and the electric meter. How much current can the 1 foot take? How is the 85A for 75C temp measured or computed?
  34. S

    Carrying capacity of power grids - USA and others

    If some technology (such as versions of fusion power) makes generating electric power vastly cheaper, will it be necessary and expensive to increase the capacity of current power grids in the USA and other countries? Or is it the case that current power grids have a lot of excess transmission...
  35. J

    Debye Approximation of Heat Capacity in 1D

    So really i am just unsure how to answer the last part of the question. I am unsure how to apply the low and high temperature limits the way i have done it. Do i set upper/lower limits on the integral and solve? If so i am not sure what to put Here is what he book has for 3d
  36. theycallmevirgo

    How can I evaluate the carrying capacity of a quadruped/hexapod robot?

    How can I predict carrying capacity of something like this ? or this? Clearly some combination of servos must defeat mg, but how many? Do all of them need to be powered constantly, whether any leg is moving or not, just to "stand up straight"? Further, each leg is clearly a lever. What is...
  37. greg_rack

    Time constant of a discharge RC circuit, capacity and charge

    So, the only thing which came to my mind in order to solve this problem was actually to write down the equations using the discharge function, being given two instants and their corresponding charges... but doing so I'm unable to find anything. Ideally, I'd say I should find the time constant...
  38. A

    Heat Capacity of a Van Der Waals' gas in an Open system

    In our class, we're using Wassermann's Thermal physics as textbook. I always try to solve all question which included in Text book. But sometime when I meet a problem that look like easy but actually hard, I'm so embarrassed. This problem do also. First, in the textbook grand potential for van...
  39. cwill53

    Specific Heat Capacity Derivation

    The specific heat capacity at constant volume and the specific heat capacity at constant pressure are intensive properties defined for pure, simple compressible substances as partial derivatives of the functions u(T, v) and h(T, p), respectively, $$c_v=\left ( \frac{\partial u}{\partial T}...
  40. HelloCthulhu

    Charge Capacity of an Electrode Based On Its Material

    Recently I've been researching parallel plate capacitors and was wondering what effects the material had on the charge capacity of the plate. I found one source for measuring the capacity based on its material, but haven't seen any textbook evidence to support it yet. Any feedback on the...
  41. TechieDork

    Need help with calculating a Cv in PHYWE's Heat Capacity of gases

    I've conducted this experiment yesterday. The main goal of this experiment is to find a gas constant R and compare it with its theoretical counterpart but I get stuck in calculating a Cv so I tried to find out what's wrong with my calculations by trying to calculate a Cv from the given data...
  42. L

    Cost Estimation capacity exponent formula

    To estimate the cost of an item of equipment or plant from another of a known cost and size or capacity , we use a well known formula Cost B = Cost A * ( CapacityB/Capacity A)^n, where n is a factor usually around 0.5-0.8 depending on the plant or equipment involved. These exponents are...
  43. Yashi234

    Max lifting capacity for an average human adult

    I have situation where i have drawn a concept with 1 sheet covering width of box for model. But now i need to draw up the manufacturing drawings and it needs to lifted and assembled by 2 people. So i need to know if person weighs 70 kg how much weight they can lift without using mechanical aid...
  44. S

    Motherboard specs - capacity for M1 SSDs?

    What language in a motherboard's specifications reveals how many sold state hard drives it can support that use the "M1" interface. Is there now an "M2" interface?
  45. Like Tony Stark

    Determine the heat capacity at a constant volume for a Van der Waals gas

    Hi, what I've done so far is solving equation 2) for ##U##, and replacing what I get in equation 1). Then, ##c_V## is equal to the partial derivative of ##S## with respect to T times T, so I've done that. The derivative is ##CNR/T##, so ##c_V=CNR## but those aren't the correct units for ##c_V##.
  46. T

    Grade 9 Physics (Heat fusion, Heat Capacity)

    Q1=2.5(390)(90-30) =58500 Q2=2.5(4000) = 10000 Qtotal = 58500+10000 Q=68500 =6.8x10^4 my teacher sent this as a homework but the options were 4.9x10^4 J 1x10^4 J 6.8x10^5 J 5.9x10^4 J im confused is is this a typo or did i do something wrong
  47. Spinnor

    Misc. Use household items to approximate human lung capacity

    I would like suggestions for using household items to approximate human lung capacity. Thinking my lung capacity was at issue (quick research showed it to be about 4.8 liters) I thought how I might measure it using household items and I came up with the following. The opening of a thin plastic...
Back
Top