Internal Definition and 957 Threads

Homework Statement Homework Equations The Attempt at a Solution Hello, my problem seems to be that I have two values that are possible for the Force FG, but I also am not considering the internal forces F_DE and F_FE. I'm not sure how to go about finding those if they are important for...

In an isobaric process of 1 mole of a monatomic ideal gas, the pressure stays the same while the volume and temperature change. Let's take an isobaric expansion where the volume increases by 2m3 and the pressure stays at 5kPa. If the work done by the gas is the pressure times the change in...

17x10^5 joules are absorbed by an expanding gas that does 8x10^5 joules of work. (a) Find ΔU; (b) Assuming it expands at constant pressure, what's the change in volume? Am I correct to use this: ΔU = Q - W Then after finding ΔU, PΔV = Q - ΔU Or does this make no sense?

For incompressible substances you have a change in internal energy represented by ΔU = mcΔT where T is temperature. I've also seen ΔH = mcΔT and ΔQ = mcΔT where H and Q are enthalpy and heat, respectfully. Does that mean that all of these are the same? I heard H becomes U...

So I have a question or two that I've wondered about for a while and am hoping that this is the right forum to (maybe) get some answers. The thing I've been wondering about is how important the visualization process is in dealing with more abstract, theoretical problems, especially as it...

Hello, this is my first post to this site. I had this idea a few nights ago, and I've been trying to wrap my head around it. Before I go ordering supplies to run some tests, I thought it would be worthwhile to gain some insight from you guys. Anyways, as you probably know, total internal...

Hello all, So the total internal energy of a gas as far as I've been told is 3/2(NKT) but it can also be written as 3/2(PV). Why then is the internal energy only a function of temperature and not volume and pressure as well? Thanks in advance for the help.

This is the example 2.12 from "Introduction to Chemical Engineering Thermodynamics", 6th. ed, by Smith, Van Ness & Abbott: "An evacuated tank is filled with gas from a constant-pressure line. What is the relation between the enthalpy of the gas in the entrance line and the internal energy of...

Hello, this is my first post, so I apologize in advance if it's not quite up to par. Homework Statement A gas is compressed at a constant pressure of 0.639 atm from 5.41 L to 2.3 L. In the process, 470 J of energy leaves the gas by heat. a) What is the work done on the gas (J)? b) What...

I had a question : Heat energy was supplied to melt ice at -15 degree Celsius. But it was not enough to turn the ice completely into water at 0 degrees. From my calculation I obtained that a mixture of 60% water and 40% ice was produced as a result of heating. Finally it said to describe...

Homework Statement I have a section of carbon steel pipe that was used to transport crude oil. The inside diameter is 24-inches. A blind flange and plumber's plug are being used to seal the pipe off. The length of the sealed section is 160-feet. Two 10 pound blocks of dry ice were placed...

I am doing a simple thermodynamic analysis. Couldn't get thermodynamic values (such as internal energy, exergy, and so on) from common data base of CO2. I looked it up in REFPROP(By NIST) and EES. None of them have data below 212K. At one atmosphere CO2 sublime at about 195K. Could anyone...

You can read just bold, or all for further info. :D The COP for a single stage vapour compression refrigerator increases with an increase in evaporating temperature. I would like to to know how it is achieved in reality with the use of an internal heat exch. on the evaporator. Can anyone...

I understand that a cylinder oriented vertically and bearing a load can be made more resistant to buckling by adding pressure to the (closed) cylinder. For example, an unopened can of soda pop can bear much more load than an opened soda pop can (I found a youtube video showing an unopened can...

Hi. I am needing help on this... For a Year 12 physics assignment (australia), I am testing a Spud gun/lemon cannon. I need to work out the pressure inside the chamber just before the projectile begins to move, without using a pressure gauge. Tomorrow i'll be measuring the muzzle velocity using...

Ok, if it says that change of internal energy is part(for example 1/3) of TOTAL work executed over system(body). Does it mean that is TOTAL work indeed sums of every single work(mechanical work+internal energy change+...) ?

Homework Statement A multi-mode fiber optic cable has a core diameter d = 115 mm, ncore = 1.42, and ncladding = 1.17. What is the largest possible angle θin relative to the surface normal that light can enter the fiber (i.e. pass from air into the fiber core) and experience total internal...

Homework Statement Homework Equations ƩFx=0 ƩFy=0 ƩM=0 The Attempt at a Solution FBD of the entire thing: ƩMB = 780(0.3) + (5/13)T*(0.72) - (12/13)T*(0.6) = 0 T = 845N ƩFx = Bx + (5/13)*845 = 0 Bx = 325N ← ƩFy = By + (12/13)*845 = 0 By = 780N ↓ Now here is where I...

Has anyone ever built an internal combustion engine which runs on solid fuel? A system would have to use waste heat or a mechanical friction device or whatever to heat the fuel and produce vapor which would be burnt in the cylinder (similar to the way coal gas was produced). Of course the vapor...

The heat transfer equation is Rate = k•A•(T1 - T2)/d where k is the heat transfer coefficient of the material. But I'm feeling that the other material transferring the heat should be important too. I mean if I were to touch Styrofoam at 50 degrees and metal at 50 degrees, the metal feels...

Homework Statement Q.1)A gas cylinder is lifted from the ground floor to the first floor.What is the amount of work done on the gas?What is the amount of work done by the gas?Is the internal energy of the gas increased? Q.2)When we place a gas cylinder on a car and the car moves,does the...

Homework Statement A force F is applied on a block of mass M.The block is displaced through a distance "d" in the direction of the force.What is the work done by the force on the block?Does the internal energy change because of this work? Homework Equations The Attempt at a...

Given the following equation of state and C_p = 3R, find the equation of the internal energy in terms of T and V p(V-b) = RT Any clues? I can use also the specific heat at constant pressure or volume. Thanks!

I'm trying to verify that some hyperlastic models I got from uniaxial data work in ANSYS. To do so, I am using a one-element uniaxial simulation (which works perfectly), and then I also wanted to do a simulation of another type of problem that I could solve analytically, to compare the results...

Can anybody tell the stress developed during extrusion of Al Alloy. More importantly, is there a type of Al alloy that prefer least amount of stress.

Homework Statement Estimate the minimum proton lifetime from the fact that you haven't yet died from internal radiation. Use the following conditions: 1.) At a dosis of Dmax = 2 Greys per year (Jkg-1 yr-1) you would already be dead. 2.) The human body is made mostly of water. 3.) The total...

Homework Statement A battery with an emf of 60 V and an internal resistance (r) is connected to a 10 ohm external resistance. The power lost inside the battery is 50w. The same battery is then connected to a 4.0 ohm resistance. The power loss is 200w. What is the internal resistance of the...

Homework Statement Consider a pump that is required to compress air in a factory. The cylinder in the pump has an inner diameter of 2.00 cm and length 60.0 cm. Air is drawn into the pump at atmospheric pressure and 18°C and the pump adiabatically compresses the air to a pressure of 17...

1. A battery whose emf is 6.0 V is connected to a 2.0 Ω resistor. The voltage drop across the 2.0 Ω resistor is 5.0 V. What is its internal resistance? a) 0.40 Ω b) 1.7 Ω c) 2.4 Ω d) 2.5 Ω Homework Equations VT=ε-Ir The Attempt at a Solution I know that ε=6.0 V VT=5.0 V...

Homework Statement Argon is a monatomic gas for which all the internal energy of the molecules may be considered to be translational kinetic energy. Molar mass of argon = 4.0 x 10-2 kg. The Boltzmann constant = 1.38 x 10-23 J kg-1 . The Avogadro constant = 6.02 x 1023 mol-1 ...

what is the change In internal energy of an ideal gas when it is expanded Adiabatically from (p °,v°) to ( p,v )? The relevant equations : dQ= dU+ pdv ; pV^ r = K (constant). r = Cp / Cv. Attempted solution : During adiabatic process dQ=0 ; p= k v ^ -r Th f r : du= -k v^ -rdv Integrating...

Homework Statement When the striking ray is held perpendicular to the prism, there are four general configurations possible (in the attachment below). Use the figure on the next page to determine analytically which of these four configurations will result in total internal reflection of the...

Hi, I regard an equation for an canonical ensemble. I do not understand why both equations should be equal. \bar{E}= -\frac{ \partial \ln{(Z)}}{ \partial \beta} \overset{\text{?}} = k T ^{2 } \frac{\partial \ln{(Z)}}{\partial T} Z is a canonical partition function. \beta = \frac{1}{kT}...

Homework Statement What is the emf of the battery shown? there is an external resistance of 2.50 ohm and 4.0 A...The battery has an internal resistance of 0.50ohm Homework Equations V=Ir V= E +/- IR The Attempt at a Solution Since the current is going away the battery then i...

what are the internal force in the hinged member 1-4?

Hi, i regard a Brownian Particle connectet to a Spring and there is a heat-reservoir. The distribution of the x-coordinate of the particle follows the Diffusion-Equation (Fokker-Planck-Equation): \partial_{t}P(x,t)=\frac{D}{2} \partial_{x}^{2}P(x,t)- \Gamma\partial_{x}[f(x)P(x,t)] A...

Two Batteries In Series--Total EMF and Internal Resistance Homework Statement Two 1.50-V batteries—with their positive terminals in the same direction—are inserted in series into the barrel of a flashlight. One battery has an internal resistance of 0.260 Ω, the other an internal resistance of...

How to relate the radiation pressure to the internal energy of an object?? How to get that formula P=u/3?? http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law#Thermodynamic_derivation Thank you.

Hello, I'm having difficulty trying to understand internal resistance of any component. I don't understand how exactly the internal resistance affects the current and what exactly is the terminal pd? And for calculating resistance, voltage, pd, emf, current and all those basic things -...

I recently encountered circuits with the source having internal resistance, and it became confusing applying Kirchoff's Rules. What I did is this: assuming the loop is counter clockwise: -------wire - negative terminal +positive terminal (conventional flow) when...

Homework Statement The critical angle for total internal reflection for a substance is 58.0°. What is the polarizing angle for this substance? Homework Equations Index of refraction: n = 1 / sin(θ_{c}) and n = tan (θ_{p}) The Attempt at a Solution So I plugged in the numbers for...

As we know, spin is an internal symmetry. but it seems a bit different from other internal symmetry, e.g. electrical charge, color, flavor... because it can be coupled with orbital angular momentum and in some aspects be linked to space-time. further more, we can classify all the particles into...

Homework Statement Homework Equations The Attempt at a Solution I got a simple circuit with an oscilloscope, a SG (with internal resistance), and a variable resistor. r and R are in series. for V_R=V_0*(R/R+r) I measured a series of R and V_R values from the oscilloscope. Now, I'm supposed to...

I have three temperatures (temperature of the fluid going in, temperature going out, and the temperature of the surface of the tube). What I'm trying to figure out is the film temperature at which I should evaluate the flow properties. The film temperature is defined as T,f = (T,s +...

Homework Statement Expression for the entropy and internal energy of black body radiation. Using the below relations: Homework Equations Total free energy for black body: $$ F = (k_b TV/\pi^2) \int k^2 ln[1-exp(-\hbar ck/k_b T)]dk $$ Relationship between partition function and internal...

Homework Statement I've been given the above truss and have to analyze it's internal forces as part of the problem, the other part of the problem is to analyze for which lengths members will fail, in what order and for which force F, however this is not the part that I find difficult. In...

Homework Statement Plane monochromatic light wave with intensity I 0 is incident normally on an opaque screen with a circular hole. What is the light intensity I of the screen at the point for which the hole: a) is the first Fresnel zone, the inner half of the first zone, b) made ​​equal...

Homework Statement For those who are not interested in reading through the different values I get for each stage then please answer this question: What is the internal energy at state 1? When water is a saturated steam... Is it U_vap + U_liq since saturated steam has both liquid and...

What are the formulas for entropy and internal energy in Fermi-Dirac statistics, and how do I derive them?

1.While studying the thermodynamic properties of perfect gases I saw that the change in internal energy for constant volume process is mCvdT. but it is also the same for const pressure, const temp, const entropy and other reversible non-flow processes. Why is it so?? why it is not mCpdT for...