Specific Definition and 1000 Threads

  1. K

    Specific heat capacity coursework

    Homework Statement earlier today i was doing some coursework to find the specific heat capacity of an unknown metal by submersing 100g / 0.1kg of the metal in boiling water above 75°C and record the temperature after 30 seconds (θm). we then had to transfer the the metal from the boiling water...
  2. S

    Specific Heat and its relevance to Molecular Configuration

    Hello, this is one of the problems in my laboratory manual and it has been killing me. I've been working on this all week. It's due tonight, so hopefully it's not too late... 1. Homework Statement Explain why specific heat is "specific", and how it gives a relative indication of molecular...
  3. TheNoobie001

    No specific questions here, *All* opinions welcome

    Hello everyone, my name is Evan operating under 'thenoobie001'.[this is also my xbox gamertag if there are any CoD fans out there :)]. I have recently joined this site and I anticipate that I will be doing a lot of forum searching and reading here at the beginning of my membership since my...
  4. R

    Specific heat/equilibrium in three component system (Thermo)

    Homework Statement Rather than retyping the problem, I've uploaded a screenshot here >> http://imgur.com/EB5MrtP Homework Equations Q_1 + Q_2 + Q_3 ... = 0 mc \Delta T = Q The Attempt at a Solution a. Q_{tea} + Q_{met} + Q_{cr} = 0 I converted the temperatures to K, so T_{cr} and T_{met} =...
  5. A

    Calculating Heat Transfer: Specific Heat Homework"

    Homework Statement Homework Equations Is my work right? This is the last attempt I got :/ The Attempt at a Solution Specific heat of water = 4.187 J/g.K Heat released by hot metal = mass x specific heat x temperature change = 99 x c x (100 - 21.4) = 7781.4c Heat absorbed by water = mass x...
  6. J

    Distributions & test functions in specific applications

    I have a question inspired by a recent thread that I did not want to hijack (https://www.physicsforums.com/threads/distributions-on-non-test-functions.831144/) I realize that weaker requirements on the space of test functions results in a more restricted set of distributions. For example, if...
  7. L

    Why Can't We Cancel (x-2) in the Inequality 2(x+3)(x-2)/(x-2)≥0?

    So given the problem 2(x+3)(x-2)/(x-2)≥0 How come we can't factor x-2 in the numerator against x-2 in the denominator? I mean theyre all just factors right? Does it have something to do about it being an inequality? We got this problem on a test yesterday, and the correct way to solve it was to...
  8. C

    Specific heat capacity (the very basics)

    The specific heat capacity is the amount of heat energy needed to raise 1 kg of a substance by 1 °C. Q. So the specific heat capacity of water is 4.184kJ (given that 1 Cal (large calorie aka the kg calorie aka the food calorie) is required to do the same, ie, raise the temperature of 1 kg of...
  9. Jabran Shakil

    Kinematics 1-D Problem. Stuck on specific parts.

    Two cars start from rest at a red stop light. When the light turns green, both cars accelerate forward. The blue car accelerates uniformly at a rate of 3.1 m/s2 for 3.7 seconds. It then continues at a constant speed for 12.5 seconds, before applying the brakes such that the car’s speed decreases...
  10. J

    Finding elements in GL_2(R) with specific orders

    Hi, Is there a way to find elements in ##GL_2(\mathbb{R})## with an arbitrary order other than by trial and error? Suppose I wanted to find ##A\in GL_2(\mathbb{R}):\; o(A)=165##. Is there no methodical way to find this? Is it possible perhaps I can find a product of matricies, each...
  11. Pouyan

    Specific heat capacity of calorimeter

    I've got a problem: A piece of copper with mass m1 = 800 g and temperature t1 = 80 ° C is placed in a container with good thermal insulation. The vessel initially contains water with mass m2 = 500 g temperature t2 = 20 C. What is the calorimeter (including thermo meter) heat capacity if the end...
  12. V

    Specific heat capacity of metal

    Homework Statement I have 1.5 kgs of silicon with temperature 40 degrees celsius. It is dropped into 3 kgs of water holding temperature 25 degrees celsius. The system is heat isolated from the environment and the final temperature of the system is 26.2 degrees celsius. I need to find the...
  13. P

    Specific Heat and Helmholtz Free Energy?

    I'm wondering if there's a simple relation between the specific heat capacity (at constant chemical potential) and the Helmholtz Free Energy? I can't seem to find a relation in the literature between these three quantities, specifically.
  14. G

    C: Printing specific elements of a structure

    Homework Statement I have the following code which manipulates with basics of structures. There are function like reading and sorting data from structures. Now, I don't know how to write a function that reads name and surname of an author of a book, and then prints data about books that are...
  15. S

    Solving Unexpected Integral Problem with Bessel Functions

    Hello! I've got unexpected problems with this very integral. I've looked through "gradshteyn and ryzhik" and found similar, but not the same. So the result, as i think, will be Bessel functions or so. Wolfram Mathematica could not calculate it, so i thought you would help with it, because it...
  16. RyanH42

    Dark Matter density given specific location

    I am doing research and I need to find the dark matter density of Galaxies or dust clusters (It can be any type of thing) which the distance from Earth will be ≅4000 Mpc.Here the picture Think the radius of sphere.
  17. A

    Amount of salt needed to achieve a specific density of soln?

    Everything as follows: I'm looking to calculate the amount of NaCl (rho=2.19 g/cm^3) needed to add to water (rho=0.999 g/cm^3) to achieve a solution with density=1.071 g/cm^3. Ideally, I want to achieve an Atwood Number of 0.035 and a density of 1.071 g/cm^3 is what I need for the solution...
  18. S

    Help finding some specific elements for infrared (IR) sensor

    Dear Everyone, I'm searching for some specific elements for infrared (IR) sensor, such as Thermopile, Pyroelectric, Bolometer, MCT(HgCdTe), PbSe, or InSb sensors. Does anyone know how to get these kinds of elements ? ( I need some information about the manufacturers...) The elements are...
  19. J

    Rocket Specific Impulse vs Jet Engine Specific Impulse

    I really can't seem to wrap my head around why the specific impulse on a rocket is so much lower than that on a jet. I know a jet engine has a larger supply of oxygen, but I don't see why that has such a huge effect. I also know exhaust velocity plays a large part, but I would have thought that...
  20. D

    Force Transform Applying: Question on a Specific Case

    When I try to apply the force transformation (the 3 vector one) to the describe following situation, I find a result that I can't make sense of. Hopefully someone can tell me what I'm doing wrong. Suppose observers A and B are in inertial frames, and B travels in the +x direction relative to A...
  21. P

    Finding magnitude of electrical field at specific point

    Homework Statement [/B] Two point-like charges are placed as shown in the figure, r1 = 28.0 cm and r2 = 56.0 cm. Find the magnitude of the electric field at point (p) shown in the figure. Let q1 = −13.0 µC, q2 = +30.0 µC. Homework Equations [/B] E1 = k*q1 / r^2 3. The Attempt at a...
  22. dbaier

    Does cooked meat aroma cause specific physiological response?

    I have been exploring (with limited success) if/how the smell of cooking meat produces known physiological responses (beyond Povlov's behavioral conditioning/salivation, but rather what known components actually trigger the response). Looking for some expertise in biology to get me on the right...
  23. I

    Why Does Iron Have a Higher Molar Specific Heat Than Its Debye Value?

    Why does iron have molar specific heat greater than Debye value 3R?
  24. D

    Specific weight and volume question

    Homework Statement So I have a problem/question were tanks are filled with water and its specific weight is 9.45 kN/m^3. They also give you a range of volumes of different tanks. The problem then asks for the plot of added weight (kN) due to the liquid for the given range of the different tank...
  25. D

    Specific weight and volume question

    So I have a problem/question were tanks are filled with water and its specific weight is 9.45 kN/m^3. They also give you a range of volumes of different tanks. The problem then asks for the added weight (kN) due to the liquid for the given range of the different tank sizes (diameter). My...
  26. M

    Energy for heating the air to a specific temperature

    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...
  27. M

    Find the molar specific heat for each gas.

    Homework Statement A mixture of two ideal gases, the first one atomic and the second two atomic are put in normal conditions in a calorimeter with volume 1 liter hermetically closed. After it is given 10J thermal energy the mixture temperature is grown 14.2 K. Find the molar specific heat for...
  28. T

    Determination of specific heat in a reaction

    Is there a way to determine the specific heat of a reaction before said reaction is introduced. thanks in advance for all of your inputs.
  29. J

    T/F The specific heat of copper is about 3R

    Homework Statement This was a problem I had on a stat mech exam awhile ago and I never figured out how to answer it. It asked "True or false, the specific heat of copper at room temperature is approximately ##3R##". Homework Equations $$C=\frac{Q}{\Delta T}$$ The Attempt at a Solution...
  30. 1

    Debye's T^3 Law: Specific heat, Latice and Electronic terms

    Homework Statement QUESTION ADDED AS ATTACHMENT AS NEED TO SEE GRAPH. Homework Equations C = (12NkBπ4/5)(T/θD)3 for T<<θD C = 3NkB for T>>θD The Attempt at a Solution a.)[/B] So I assume the expression for the specific heat as a function of temperature that the question must want: C =...
  31. E

    How to know the shape of a specific location on Earth?

    How do you know the shape (land altitude, roughness, etc.) of a specific location on Earth through a satellite? For example, if a specific place is covered by clouds is there a way to know the shape of the ground at this specific point? I have read through the absorption spectra of the...
  32. I

    Standing wave with specific initial/boundary conditions

    Homework Statement "Solve the wave equation with the following initial conditions and boundary conditions." ∂2Y/∂x2 = 1/v2 * ∂2Y/∂t2 Boundary conditions: ∂Y/∂x(x=0, t)=0 and Y(x=L,t)=0 Initial Conditions: ∂Y/∂t(x, t=0) = 0 Y(x,t=0) = δ(x-L/2) Homework Equations Using separation of...
  33. A

    Calculating DFT for specific polynomial

    Hello everyone, This seems like a simple problem but I get the impression that I'm missing something. 1. Homework Statement Given the values ## v_1,v_2,...,v_n ## such that DFTn ## (P(x)) = (v_1, v_2, \ldots, v_n) ## and ##deg(P(x)) < n##, find DFT2n## P(x^2)## Homework EquationsThe Attempt...
  34. L

    Specific heat capacity of gases

    Homework Statement Figure shows two rigid vessels A and B, each of volume 200 cm3 containing an ideal gas (Cv = 12.5 J/mol-K). The vessels are connected to a manometer tube containing mercury. The pressure in both the vessels is 75 cm of mercury and the temperature is 300 . (b) 5.0 J of heat...
  35. MexChemE

    Converting humidity ratio to specific humidity

    Hello PF! I have a very simple question on psychrometry. I had an argument with one of my professors regarding these two quantities, humidity ratio and specfic humidity. Humidity ratio is defined as mass of water vapor per unit mass of dry air. It's the one you can read from a psychrometric...
  36. Eclair_de_XII

    How do I find the specific heat of a hot object in water?

    Homework Statement "Using the above calorimetre with 100.0 g of water of in it at 20.0°C, a 50.00 g sample of a metal at 100.0°C is added. The temperature of the calorimetre rises to 27.2°C. What is the specific heat? (S.H. = 0.20 cal/g°C)" Homework Equations Heat capacity of calorimetre used...
  37. D

    Specific heat capacity and changing volume

    Hello everyone, I just need some help understanding some thermodynamics. So I have 0.25 kg of helium which is compressed from an initial state in a polytropic process with n = 1.3. So its given the change in volume and the initial pressure. I need to find the change in internal energy. I am...
  38. M

    Importance of GPA vs specific grades

    I'm in the UK system and will probably graduate with a high 2:1, missing out on a First Class Honours due to mediocre grades in my early years due to burnout and lack of interest. However, the grades in the areas I'm interested in are quite good - high first class honours grades in each one, and...
  39. A

    Hydrogen and it's Specific Heat.

    Hello, I had a few questions regarding hydrogen. I know for a fact that hydrogen has a high value of specific heat. My questions are: 1). Isn't hydrogen supposed to be a good coolant, and if it is is it actually used ? 2). If it is a good coolant how does it work as a fuel ? I hope these...
  40. J

    Need help solving a specific PDE

    A[t] = ΣΣukvjpnmt ΣΣpnmt = 1 and A[0] = p000.
  41. S

    Specific Heat at constant pressure for photon gas

    Homework Statement A blackbody photon gas is contained within an evacuated cavity (V = 0.01 m^3). Calculate C_p for the photon gas at T = 1000K Homework Equations C_p - C_v = T(\frac{\partial S} {\partial V}) (\frac{\partial V}{\partial T}) C_v = T(\frac{\partial S} {\partial T}) S =...
  42. R

    Specific heat capacity ; voltage ; heating water

    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...
  43. J

    How to get specific frequency and time values for .wav file

    How to get specific frequency and time values for .wav file and export the values as .csv? Problem: I need to analyze this music .wav file, particularly for its frequency, amplitude, and pitch over specific intervals of time. Is there any easy to use software and steps I can take that can...
  44. A

    Dipole moment of a specific charge distribution

    A negative charge cloud distribute as a ellipsoid and a positive point charge situated at the centre of the ellipsoid.What should be the dipole moment of charge distribution.I mean, if the negative charge distribution is spherical and positive point charge at the centre then surely dipole moment...
  45. evinda

    MHB Find solution that satifies the differential equations and has a specific form

    Hello! (Smile) I am looking at the following exercise: Let $I=(0,1)$. Find the solution $\phi$ that has a continuous derivative in $\mathbb{R}$ and satisfies : $$y''=0 \text{ in } I \\y''+k^2y=0 \text{ apart from } I, \text{ where } k>0$$ and furthermore $\phi$ has the form...
  46. X

    What is the specific activity of the air inside the sealed warehouse?

    Can anyone please guide me how to find solution of this problem A 0.2-g sample of 85Kr gas, which decays into stable 85Rb, is accidentally broken and escapes inside a sealed warehouse measuring 40×30×20 m. What is the specific activity of the air inside?
  47. S

    Fortran Fortran 90 command to write only specific lines

    Hi all. I did search in internet but couldn't find the specific answer for my specific problem.I need to run a program with a datafile in 3000 time step and the output will 1.dat to 3000.dat, which is every single data output size 200Mb. To safe the storage, I would like to write only every...
  48. B

    Derivations of specific values in Physics

    Homework Statement I am wondering if anyone knows of a document that shows derivations of specific values in Physics? For example, I need to find μs and am given the distance traveled and time (1.2 km in 17 sec). Homework Equations I know the equation for μs, Ffriction=μs⋅FN. The Attempt...
  49. Muhammad Nauman

    Specific heat capacity of Gd5Si3 and GdSi

    Hello alll. I am Muhammad Nauman, Research Associate in COMSATS university islamabad pakistan and new in this group. I need Specific heat capacities of Gd5Si3 and GdSi. Can someone help me??
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