Internal Definition and 957 Threads

Can you help me with this problem? An ideal gas is compressed adiabatically. The work done over it is 200 J. How much will the internal energy change? A) 200 J B) 100 J C) -200 J D) 0 J Which formula do you use to solve it? Thanks in advance!

1. A gas bottle with a volume of 0.1 m3 contains 0.4 kg of a gas at a pressure of 7 MN/m2 and a temperature of 150 ºC. For this gas Cp = 10.54 kJ/kg K. Calculate the changes in internal energy when temperature is raised to 500K Given answer: 362 kJ 2. pV=mRT pv=RT...

Just had a thermodynamics exam, and one of the questions was For an ideal gas, is the relation \DeltaU = mC_{}v\DeltaT restricted to constant volume processes only? Why? I wrote that it was only valid for constant volume processes, because this is what C_{}V is defined as, however now I'm...

Hello all, I am confused with naming of the Zeeman effect (in nuclear or/and electronic levels). Is that means: 1. splitting of spectral lines due to internal magnetic field, or 2. splitting of spectral lines due to external magnetic field, or 3. splitting of spectral lines due to...

I'm working from Feynman's definition of internal energy for the Debye theory of heat capacity. I'm trying to use that to derive the normal definition of heat capacity that I've seen. But I'm running into a problem. Note, in the following V_0 is frequency, whereas V is volume (that's how Feynman...

What's the difference between enthalpy and internal energy? Internal energy is the average of the kinetic energy (linear and angular) of the particles of the body (or system), right? Could someone explain me this clearly? Thank you

Homework Statement A 15.0 kg block is sliding across the floor. Initially, it is moving at 1.2 m/s. However, after sliding 20.0 meters, =7.5 J of work are done on it by friction. What is the block's velocity after sliding 20.0 meters? Homework Equations KE=.5v2 lw-l=F\DeltaXcos\theta...

Homework Statement A plane wave is incident at 70˚ to surface normal traveling within a medium with relative permittivity = 4, striking the boundary with air. Where is the nearest magnetic field max. to the boundary in the initial medium? Find the 1/e penetration depth of the evanescent...

Just like the title, does battery capacity depend on internal resistance? I know it does depend on the temperature and the chemical structure of the battery, but does it also depend on internal resistance? If so, how dependent are batteries on internal resistance? Also, what is the...

Homework Statement Prove that D4 (Dihedral group) cannot be expressed as an internal direct product of two proper subgroups. Homework Equations The Attempt at a Solution I know that the only two possible subgroups would be the subgroups of order 4 and 2. I am thinking since D4 is...

Homework Statement What is the maximum value of θ1 that would cause total internal reflection to occur? N1 = 1.3, n2 = 1.6 (picture attached) Homework Equations Critical angle = sin^-1(n1/n2) The Attempt at a Solution I figured the critical angle to be 54.3. That means that...

I'm currently doing a project on neural network controller for an internal combustion engine to reduce emissions level. Can anyone assist me in training such models (neural networks)

Hi guys. I am working on making a haptic device for a baseball simulator. Now the problem is that I want to replace the external force for the ball hitting the bat with an internal force in my bat-like device using either solenoids or motors. Do you think it is possible to replace the external...

What is the relationship between viscosity and convection in the mantle?

Question about internal energies... PLEASE HELP ME! What must be true for two objects of the same material to have the same internal energies? (Choose all that apply) a. The masses of both objects must be equal b. Both objects must have the same density c. The temperatures of both...

I have an issue I'm not quite sure how to approach. A customer is requesting that we prove that our battery pack chassis will not burst or deform if additional gases are introduced inside the enclosed box (the batteries could vent). The chassis is assumed to be a sealed .05" thick 5052 AL...

Homework Statement I have two identical volumes of gas, and I heat them both to 100 C, one under constant pressure, one under constant volume. Which has more internal energy after the process? The attempt at a solution I believe that they both have the same as the extra heat you have...

Okay, so I've found this site (http://www.spiritofmaat.com/archive/feb2/carplans_doc.htm) and it claims to have a reliable method to convert a diesel engine to run off of hydrogen. Now, my question is is this actually feasible in the method they've described? I've asked two other sources and so...

There are a couple of products on the market which allow you to attach an external desktop gpu to the laptop and then use an external monitor and play games using the the desktop gpu instead of the weaker gpu in the laptop. It's a great idea but it means that you must carry an external...

Homework Statement A car of mass 2200 kg collides with a truck of mass 4500 kg, and just after the collision the car and truck slide along, stuck together, with no rotation. The car's velocity just before the collision was < 35, 0, 0 > m/s, and the truck's velocity just before the collision...

Homework Statement There's .1 mole of an ideal gas trapped in a cylinder with a movable piston. If Pi= Pf= 5000Pa, Vi= .04 m^3, Vf= .08m^3, Q=500J,,,Find W, change in (U), Ti and Tf. Homework Equations change in U = Q+W W= -p change in V The Attempt at a Solution W= 200J...

Is the internal resistance of the battery or other source is variable or not? without discharging . Is it depend upon on the external resistance?

Homework Statement 2 moles of a monatomic ideal gas expands from state A to state B. PA = PB = 600 N/m2, VA = 3.0 m3 and VB = 9.0 m3. i. Calculate the work done by the gas as it expands. ii. Calculate the change in internal energy of the gas as it expands. iii. Calculate the heat added to or...

Homework Statement Two bodies of mass M and m separated by a distance 'R' are released and they move towards each other under the influence of gravity . What is the work done by internal forces (considering the 2 bodies as a system) when they are at a distance 'x' apart ? The Attempt at a...

A battery labeled 12.0 V supplies 1.90 A to a 6.00 ohm resistor A) what is the terminal voltage of the battery? B) What is its internal resistance V = 12.0 R = 6.00 I = 1.90 I think i am to use V = emf - IR for terminal voltage right? however i do not know how to get emf, and IR...

Hi all, I read that the internal entropy change of a system (\DeltaSi) for a non-quasistatic process where a reservoir cools or heats the system, where N and V are fixed and no work is done is approximately equal to (\DeltaT)2, when the difference between TReservoir and Tsystem is small. The...

U is internal energy, which is the sum of heat + work done. \DeltaU = q + w -----(1) where w = \Delta(PV) Enthalpy is the internal energy + work done \DeltaH = \DeltaU + P\DeltaV At constant pressure, \DeltaH = q - P\DeltaV + P\DeltaV \DeltaH = q_{p} Where q_{p} is used to...

In my book it says that the change in internal energy = Q -W Yet, my teacher says that its Q + W He says that it's reversible due to the signs... but i don't know what that means... can somebody give me an example?

Homework Statement A moves with momentum p into B at rest. The objects collide and move off with momenta p_1, p_2 at an angle (irrelevant but anyway). What are the internal forces in the system? Homework Equations F=p dot The Attempt at a Solution What's an internal force? Isn't it...

Hi there, I have some serious problems with a couple of questions. Need help for exam revision. 1.1 Homework Statement A 2kg chunck of ice at -10Celsius is added to 5kg of water at 45Celsius. What is the final temperature of the system? 1.2 Relevant equations specific heat capacity of ice -...

Homework Statement Two almost identical lead-acid accumulator batteries, X and Y, are connected with opposing polarities in a circuit which includes an ammeter, an ideal millivoltmeter and a resistor R as shown in figure below. When S1 is closed with S2 left open, the millivoltmeter reads 50...

A small source of light at the bottom face of a rectangular glass slab 2.25 cm thick is viewed from above. Rays of light totally internally reflected at the top of the surface outline a circle of 7.6cm in diameter in the bottom surface. Determine the refraction index of the glass. This is...

Homework Statement My physics teacher (i'm in year 12) set me a "challenge" to prove a graph in our textbook, which shows Power against Resistance, with a local maximum where [SIZE="3"][FONT="Times New Roman"]R = internal resistance, [SIZE="3"][FONT="Times New Roman"]r. He told me i'd need to...

Homework Statement Suppose 1 g of water vaporizes isobarically at atmosphere pressure (1.013 x 105 Pa). Its volume in the liquid state is Vi = 1 cm3, and its volume in the vapor state is Vf = 1671 cm3. Find the change in internal energyHomework Equations \Delta U = \Delta Q - \Delta W \Delta...

Homework Statement I have been stuck on the following problem for 2 days now, can anyone help? The p.d. at the terminals of a battery is 25V when no load is connected and 24V when a load taking 10A is connected. Determine the internal resistance of the battery... Thanks Homework...

I am very much confused with this statements "The forces of action and reaction never cancels out each other , but the internal forces on a system of particles cancel out in pairs " I think i know the reason for the first statement.i.e,The forces of action and reaction are acting on different...

This looks to be a much more active forum than another I tried to get some feedback on recently...same question, hoping someone here can weigh-in on this before I potentially make a mistake. I'm installing a mini PCI WLAN card (802.11n/g) and antenna inside of a small form-factor PC. The...

Homework Statement Please help with this problem! How many sprints from rest to a speed of 4.5 m/s would a 59 kg woman have to complete in order to burn off 5.0 x 102 Calories? (Assume 100% efficiency in converting food energy to mechanical energy.) Homework Equations...

hello happy new year i'm a little confused here after i saw this U= KE + PE + H(enthalpy)----------------------1 while it is known that H=U+PV------------------2 i'm sure that eqn 2 is true but do you think with m that 1 is not true ?? the problem is that my instructor use...

I’m from a group that is current working on the theory of a Hydrogen Economy. Our first area of development is the Hydrogen Highway. We are currently seeking help in the form of freelance / work for hire basically engineer(s) that could aid in design and calculations of internal combustion...

Hi, I've got a problem with collision detection of which I am struggling to find a solution. In the simplest case, I would have a sphere whose movement would be constrained inside a closed arbitrarily-shaped object. I have been looking into BSP trees which split the shape into chunks...

Homework Statement The drawing shows a crystalline quartz slab with a rectangular cross-section. A ray of light strikes the slab at an incident angle of 1=34o, enters the quartz and travels to point Po (Figure2). This slab is surrounded by a fluid with a refractive index n...

Homework Statement You have a power supply of 10 V. It is connected in series to a 2 ohm resistor and a 5 ohm resistor. You take the voltage across the 5 ohm resistor with a voltmeter that has an internal resistance of 3 ohms. What is the current through the voltmeter?Homework Equations The...

Homework Statement Have to determine permeabilities \alpha and \beta (PNa/PK and PCl/PK) as well as internal concentrations of Na+, K+ and Cl- I have calculated different membrane voltages according to the external concentration (when altering one ion, the other two were set to zero)...

Homework Statement Consider a common mirage formed by superheated air just above a roadway. A truck driver whose eyes are 2.00 m above the road, where n=1.0003 looks forward. She has the illusion of seeing a patch of water ahead on the road, where her line of sight makes an angle of 1.20...

Homework Statement The internal energy of a system increases by 200 J while 900 J of work are performed on it. What was the magnitude of the heat flow into or out of the system? Does the heat flow "out of" or "into" the system? Homework Equations Don't really need. The Attempt...

Hi there, my first post on this forum and I hope its in the right place ! My question is this, in an exisitng air-cooled motorcycle engine what is the viability of using heat pipe technology to cool exhaust gas temperature? Using heat pipes to remove heat from exhaust valve areas to external...

Basically I want to Calculate the internal resistance of a solar cell. I set up a circuit with a voltmeter across the solar cell and an ammeter and variable resistor in series with the solar cell. The variable resistor is the load. Image at...

What is the fastest speed ever recorded, achieved by a internal combustion piston engine on a land vehicle, and not an aircraft/propeller? I know that some top-fuel dragsters can exceed 300 MPH.

I want to tap a NPT (NPT-3/4) thread hole on a plate. And I found some related standards, these standards told me the detailed dimensions of the thread. My question is how to machine the NPT thread with a tap? How to control the parameter mentioned in the standards? thanks in advance!