Closed system Definition and 84 Threads

Homework Statement a fluid undergoes a reversible adiabatic compression from .5 MPa, .2 m3 to .05 m3 according to the law PV1.3 = constant. determine the change in enthalpy, internal energy and work transfer during the process. Homework Equations P1V11.3 = P2V21.3 dH = T dS + V dP dS = 0...

If not, does the second law of thermodynamics even apply? What role would entropy play if it is not?

Homework Statement A closed system containing a gas is to undergo a reversible process from an intial specific volume of 2 ft^3/lbm and a intial pressure of 100 psia. The final pressure is 500 psia. Compute the work done per unit mass. a. Pv= constant b. pv^-2 = constantHomework Equations (1)...

Homework Statement 1. A piston cylinder arrangement ( A = 0.25 m^2, P1= 200 KPa, V1= 0.05 m^3. is loaded with a linear spring. in the current configuration the spring exerts no force on the piston head. if the atmospheric pressure is 101 KPa, what is the mass of the piston head. Heat is now...

I've been researching this for quite a while and feel somewhat exasperated, so I thought I would ask more knowledgeable folk. I need to seal a closed system for low vacuum, and I need to do it on a budget. My problem is that most of the information I have found deals with much higher vacuums...

We wrap a light, flexible cable around a thin-walled, hollow cylinder with mass M and radius R. The cylinder is attached to the axle by spokes of a negligible moment of inertia.The cylinder rotates with negligible friction about a stationary horizontal axis. We tie the free end of the cable to a...

Originally posted on sciforumsDOTcom by me (DRZion): So I came up with a scenario which is simple enough for anyone to understand. You take a fluid which is liquid at room temperature, but freezes to a become a solid denser than the liquid. This is done to any amount of liquid at the...

As shown in the figure attached, an insulated box is initially divided into halves by a frictionless, thermally conducting piston. On one side of the piston is 1.5 m^3 of air at 400 K, 4 bar. On the other side is 1.5 m^3 of air at 400 K, 2 bar. The piston is released and equilibrium is attained...

While trying to get my head around Gravitational Potential Energy I devised the following simple system: Point Mass A of 1kg is 1000m away from Point Mass B of 100kg within an empty universe. The gravitational force exerted by A on B is G*10^-16; by B on A is G*10^-4. At time=0 these two...

Because of the kinetic energy and frames of reference thread: https://www.physicsforums.com/showthread.php?t=534883 I was wondering how to show that a change from potential to kinetic energy in a closed system is independent of the (inertial) frame of reference. I think the math below...

Hello, Please forgive my ignorance, although bright, I was a lousy student, & never took physics in school. I find it frustrating when relatives & friends are uncertain as to how to respond to questions like those below, so your educated reply would therefore be all the more appreciated...

A simple rotating system with no external forces acting on it carries a fixed angular momentum and an associated rotational kinetic energy. If the system changes its internal configuration, such as a spinning skater retracting or extending his/her arms, the angular momentum remains constant...

In a closed piping system (such as a chilled or hot water system in a tall building), is the water pressure at the top less than that at the bottom? Bernoulli's equation would lead you to believe that it is, but I cannot find anything explicitly stating that this applies to closed systems...

Ok this is solely for my interest. I should know this if I were taking Grade 12 Chemistry, but I haven't had this course in two years, and neither have I continued in pure science since then so please if you know better tell me if this is correct AND if it is only so because the case is of a...

Homework Statement 1kg of water that is initially at 90 degrees celsius with a quality of 10% occupies a spring loaded piston cylinder device. The device is now heated until the pressure rises to 800kPa and the temperature is 250 degrees c Determine the total work done during this process...

The 2nd law of thermodynamics refers to closed systems. 1. If we imagine a universe of infinite extent but where only one object exists that emits e/m waves, is that a closed system? 2. If we imagine a universe where only two asteroids exist and are orbiting each other, and a machine between...

Homework Statement 31.47mol of copper at 273 kelvin put inside an isolated cup along with 1 mol of water vapors at 373 Kelvin. (pressure is constant at 1 atm). ALL of the water condensed. given parameters: Cp(Cu(solid)) = 24.44 J/mol Cp(H20(gas) = 33.58 J/mol Cp(H20(liquid) = 73.35...

If I am within that closed system, can I make the rate of entropy of the entire system any faster or slower overall? Does the existence of life within the system decrease or increase the overall system entropy rate?

Would the conservation of mass apply to the universe? Sorry I looked for awhile for the answer to this question but I couldn't really find anything.

Hello, Can a closed system change the position of its center of mass if no external force is exerted on it?

Homework Statement A closed system comprising a cylinder and frictionless piston contains 1kg of a perfect gas of which molecular mass is 26. The piston is loaded so that the pressure is constant at 200kPa. Heat is supplied causing the gas to expand from 0.5m^3 to 1m^3. Calculate heat...

I have devised a simple thought experiment which leads me to an absurd conclusion and I feel I’m missing something obvious but I can't see where I’m wrong and I hope you could help point out my error. I start with an empty space initially containing two masses that are at rest relative to...

Homework Statement We have a tank with some gel and it will be emptied into another empty tank. The air in the first tank wil stay in the first tank. The air in the second tank will stay in the second tank. What is the equilibrium height of the solution inside the tank. also, see Excel...

Properties in a closed system...Help! Homework Statement A cylinder, locked by a plug, contains 1kg of 'wet' steam at a pressure of 5 bar (state point 1). In the locked position, heat is added through the wall of cylinder into the wet steam until the mixtures become dry saturated at 200...

I recently was having a discussion about entropy and the concept of the universe being an open or closed system came up. Assuming that the universe is infinite, would it be considered to be an open or a closed system? A closed system being a system in the state of being isolated from the...

Homework Statement Beaker A contains a volatile solvent and beaker B contains 10% solution of a non-volatile solute in the same solvent. Both beakers are placed in a closed environment as shown. The question asks what will happen when the system has reached equilibrium. The answer is given...

I must have already been banned for spamming threads. But oh well. You know how change in entropy dS of a closed system assuming reversibility of the processes = (\frac{dQ}{T})_{rev}=\frac{C_{p}dT}{T} So when you try to find the actual entropy with respect to temperature, it's: \displaystyle...

First post here... It seems to me (I have not read this anywhere, so forgive me if it sounds ignorant), that in a closed system, the measure of the quality we call "time" can only exist if there is a change in the form of energy or movement of something physical. For example, if I have a...

In his book, "Representations and Reality", Putnam states: How would you define an "open system" in this context? How would you define a closed system?

If you take a quart of water and take it from 60 degrees Fahrenheit to -35 degrees Fahrenheit not allowing for expansion, what is the average delta psi/degree and the delta pressure total?

Hello homework forum, I am working on some mechanical energy questions right now for Physics class, and I have a quick question. A mass (1.00 kg) is projected vertically upwards at a speed of 40.0 m/s. There is a frictional force of 5.0 N acting on the mass. The question that's bothering me...

I'm sitting in my car on a flat road while it is stationary. The only forces acting on my car for this exercise are gravity and the normal force, which add up to give no net external force on my vehicle and me. My center of mass is at a fixed point somewhere in the vehicle, and according to the...

In a closed system a hydrocarbon is burnt. The products which are produced have a temperature of X degree celcius. What will happen once the temperature of whole of the system becomes X degree celcius? How will it affect the burning of hydrocarbon? Thanks a lot for any help. Abd. S.

Question: Does the entropy of a closed system always increase, or could it possibly decrease? Answer: The standard answer to your question from the laws of thermodynamics is that entropy (disorder) will increase, but there are at least two ways I believe entropy can decrease in a closed...