Internal Definition and 993 Threads

I am going over this example 0.5 kg of air undergoes a Carnot cycle with η = 0.5. Given the initial pressure p1 = 700 kPa, initial volume V1 = 0.12 m3 and heat transfer during the isothermal expansion process Q12 = 40 kJ, Find the highest and the lowest temperatures in the...

[SOLVED] Internal Energy and Heat Homework Statement Ten joules of heat energy are transferred to a sample of an ideal gas at constant temperature. As a result, the internal energy of the gas: a) increases by 10 J b) increases by less than 10 J c) increases by more than 10 J d) remains...

This is an attempt to calculate the efficiency of a modern gasoline engine (Volkswagen's 1.6 litre FSI). The result seems too good to be true. Please let me know if there is any error. At a constant 100 km/h on a flat motorway, the consumption of my car reads 5.7 l/100 km. The engine revs...

Like in the other problem I posted- This is the other question that I missed and just can't find a solution for. Homework Statement Prove the internal pressure is 0 for an ideal gas and ((n^2)a)/(v^2) for a Van der Waals gas. Homework Equations 1. VdQ Eqn: p= (nRT)/(v-b) -...

Homework Statement "A 6.0V battery is connected across a parallel combination of two resistors ; one 10 ohm and one 40 ohm. Thee total current provided by the battery is 0.25A. Obtain a value for the internal resistance. Homework Equations E= IR +Ir The Attempt at a Solution...

Question on total reflection...if you were to conceal a coin, by putting it under a beaker whose lid is covered with foil, and you slowly add a liquid until the coin seemingly disappears, which would require a greater volume? oil or water?

An internal combustion engine runs on octane, the enthalpy of combustion is -5512 kJ/mol. The mass of 1 gallon of fuel is 3 kg. The engine temperature is 2000 degrees C and the exit temperature is 800 degrees C. What is the work done? The total enthalpy is -145053 kJ. The total number of...

I am having trouble explaining the difference between internal and external forces, and in fact, even *defining* internal forces. Does anyone understand the difference very well? My current example is: Hold an elastic band loosely between both your index fingers. Now, move your fingers...

[SOLVED] Internal energy, thermodynamics Homework Statement I have the equation for the internal energy: U = (f/2) * N * k * T, where f is the degrees of freedom, N is the number of molecules, k is Bolzmann's constant and T is the temperature in Kelvin. This can be written as U = (f/2)*p*V...

Relevant equations int rest =emf - terminal potential / current or r=E-V/I The attempt at a solution Since Emf of a cell is inversely proportional to temp (From Nernst Equation of Emf of a cell), from the above equation, if temp is high, E is low, therefore r is low. So, acc. to me...

Anyone with any idea about the basic internal design & engines in an electric car?

Hey everyone, I'm knocking my head against something and for some reason I can't get it to work out -- I'm running an N-body simulation which uses an internal gravitational constant of 1, meaning that the timestep used is a function of the units of mass, length, and velocity. But I don't know...

[SOLVED] Internal Energy Problem Homework Statement Given .15meters cubed of Helium gas at 300K and 3Pa in a chamber with a frictionless piston. How much heat is required to double the internal energy of the gas at constant pressure? Homework Equations I really don't know what equations...

Hi There, Right I recently did an experiment in Physics to find out the internal resistance of a lemon when used as a power supply. We connected the lemon to a voltmeter, ammeter and variable resistor, changed the resistance on the variable resistance and measured the voltage and current...

Internal struggles of ideas in non-string QG One should not exaggerate the internal struggles which are going on or ready to happen. But we might take note of some of the internal conflicts. Issues that will probably get worked out in the next few months----whether or not they are openly...

[b]1. A white light source is below the lower surface of a piece of optical-quality glass. The glass has an index of refraction of 1.520 for red light and 1.538 for violet. If you were able to move your eye at any angle relative to the perpendicular to the glass, calculate A) Which color...

I hope someone can help me with my coursework by making sure my method is ok and is actually correct for my experiment. Note. I will not actually be doing this it is just a plan of what I could do! 1. I am provided with a cell of approcimate EMF 1.5V, an approximate internal resistance of 1Ω...

Homework Statement this is a picture of an example from the book. I am going off of it to solve a problem that will be on my test tomorrow. i can figure out how to calculate the shear force and moment of each section (though i don't fully understand it), but I am just not getting how they...

1. Find the current in, and the potential difference across, each resistor in the circuit shown below: The circuit is a simple parallel circuit with 2.0 ohms at the first resistor, 10.0 ohms at the second, and 20.0 ohms at the third The problem also gives you Emf which is 12.0 V and the...

One mole of an ideal diatomic gas at room temperature undergoes a transition from a to c along the diagonal path in Figure 19-23. (a) During the transition, what is the change in internal energy of the gas? -4987 J (b) How much energy is added to the gas as heat? ____ J (c) How much heat is...

in the problem they give you V=44m/s, mass=.09 kg , and a vertical distance=18m the problem states that a ball is shot straight down and at the distance 18m it encounters a sand bag the ball goes through the sand bag .5 m. they ask what is the internal work neglecting friction? for this...

Homework Statement Hi, my first post here. :smile: Anyway I am struggling with this homework, can someone help me out, show me what to do please. 1)a cell can supply a current of 1.2A through two 2ohm resistors connected in parallel. When they are connected in series the value of the...

Can anybody please give me an example of INTERNAL and EXTERNAL force. I was told by my Professor that there is only internal Torque at the moment when you are running toward a marygoround and grab so of the handles. PLEASE EXPLAIN ME WHY.

For this question: http://tinyurl.com/3ahesh the answer is a. May I know how do we come to the conclusion that the net change of internal energy of the gas is zero?

Internal energy vs temperature(q37) For this question: http://tinyurl.com/3ymlnj The answer to this question is c. But according to my understanding, increasing of internal energy means increasing of temperature. Hence is isothermal situation, the change of internal energy is 0. With...

Homework Statement The potential difference across the terminals of a battery is 8.20 V when there is a current of 1.54 A in the battery from the negative to the positive terminal. When the current is 3.56 A in the reverse direction, the potential difference becomes 9.40 V. What is the...

Homework Statement This problem relates to an experiment to determine the e.m.f and internal resistance of a battery using a variable load. Taking values for V & I a graphy of V vs. I was plotted. Homework Equations E=IR+Ir V=IR The Attempt at a Solution After plotting the graph...

Regarding "Total Internal Reflection" Hi, and thanks in advance for viewing this post. I'd like to type out the question first; Q: Consider the optical interface between crown glass and ethanol. a) Under what conditions would total internal reflection be possible at this interface? Illustrate...

Hi, I have to solve diffusion-advection PDE using finite difference method. The problem has two regions with different diffusion coefficients and velocities. At the interface between the two regions types of boundary condition : 1. No contact resistance C1 = C2 - D1*dC1/dx + v1*C1 = -...

How can I design an internal combustion engine especially with connecting rod?

Homework Statement One mole of hydrogen gas is heated from 278 K to 390 K at constant pressure. Hydrogen has a specific heat of 43.6 J/mol*K. The universal gas constant is 8.31451 J/K mol. Calculate the change in the internal energy of the gas. Answer in units of J Homework Equations...

Homework Statement one mole of He, H2, CO2 goes through a process such that the change in their internal energies are the same. WHich of the gases has a higher temp change? Homework Equations Eint=3/2nRdeltaT=nCvdeltaT (for monatomic gases) Eint=5/2nRT (diatomic gases) polytamoic gases...

light refractions problem I don't even know where to start with this problem. Can someone please help me out? As shown in Figure P22.49, a light ray is incident normal to on one face of a 30°-60°-90° block of zircon(n= 1.923) that is immersed in water. Figure P22.49 (a) Determine the...

Homework Statement The refractive index of the Earth's atmosphere is: n=1.01+(alpha)(R-r) where (alpha) is a constant, r is radial distance from Earth's centre and R is the Earth's radius. By considering a path comprising a series of total internal reflections or otherwise, find a value of...

I am currently in my first year in Mechatronics Major, and now I am trying to understanding about statics of beam. How about draw the shear and moment curve? How about if the force is variation and have graph too. Just like this for example || V the curve of this like sinus or cosinus...

Homework Statement I'm having trouble with the following two problems: 1. A jar of tea is placed in the sunlight until it reaches an equilibrium temperature of 32*C. In an attempt to cool the liquid, which has a mass of .180kg, .112 kg of ice at 0*C is added. At the time at which the...

How internal reflection affect the performance of the thin film emissive display devices?

As the angle of incidence increases, the angle of refraction becomes larger. Should the underlined word be decreases? why? I think I've found a mistake in the book because according to snell's law of refraction n1sin(theta)1=n2 sin(theta)2 right? If n1>n2 then (theta)1<(theta)2 Wait, I...

While making calculations of FTIR/tunneling isn't that hard, I don't understand the phenomenon, and therefore there are some predictions I'm unable to make. So I have some questions (or it's probably just one). If you have a prism with refractive index n in vacuum, total internal reflection...

I am so lost with this question. Can anyone help? The internal energy of the gas in a gasoline engine's cylinder decreases by 176:7 J. If 67.0 J of work is done by the gas, how much energy is transferred as heat? Answer in units of J

Homework Statement Does the internal energy increase/decrease(U), quantity of heat released or supplied (Q), and work done by or on a system (W) when (a) water freezes to ice at constant temperature (b) ice melts to water at constant temperature (c) water evaporates at constant temperature...

Homework Statement Hi I've tried to solve this question but I keep getting stuck at a certain point, it probably very simple but any tips would be greatly appreciated The EMF of a cell is measured using a potentiometer and is found to be 1.51V. When a voltmeter, which has a resistance of...

Homework Statement In a circuit, two identical batteries with EMF of 22 V and internal resistance of 7 Ohm are placed in parallel to provide power to a load resistance of RL = 35 Ohms. What is the power transferred from the current to RL to heat the resistor? Homework Equations Is R(L)...

Hi everyone, We have an argument about gasoline combustion engine and diesel engine. Some say, the diesel engine is stronger than gasoline one. My idea is if the two engines are the same dimension, they must have the same power. Am I right or wrong. Thanks

I want to understand that why does the internal resistance of a cell/battery goes on increasing as the cell gets older. What happens inside the cell that causes the internal resistance to increase gradually? Thanks.

something strange happened to me recently, although this is just an anecdotal story, so i appreciate that what i thought had happened may not have been the case. anyway, I've noticed that if my alarm clock is consistently set to say, 7 AM, i will wake up roughly around that time even if I've...

1. The problem: A resistor has a resistance R, and a battery has an internal resistance r. When the resistor is connected across the battery, ten percent less power is dissipated in R than would be dissipated if the battery had no internal resistance. Find the ratio r/R. 2. Homework...

Homework Statement In the case of total internal reflection, show that the average rate of energy transport across the boundary is zero. Homework Equations None Provided The Attempt at a Solution All that I have come to is that I should use some form of the following method to find...

If I do 5 trials of measuring voltage and current of a circuit (with different resistors for each trial), how would I find the inner resistance of the power source?

A 575 kg satellite is in a circular orbit at an altitude of 550 km above the Earth's surface. Because of air friction, the satellite eventually falls to the Earth's surface, where it hits the ground with a speed of 2.10 km/s. How much energy was transformed to internal energy by means of...