Internal Definition and 993 Threads

Homework Statement Homework Equations Δu = ∫ [(a-Ru)+bT+cT^2+dT^3]dT The Attempt at a Solution The answer of 6447kJ/kmol is given but I am struggling to get to this answer after integrating the above formula and inserting the given values. Firstly would the integral of...

Homework Statement Sketch a diagram of internal energy (y-axis) versus temperature in the range from -10°C to +112°C to indicate how energy would change for a fixed quantity of water in its three phrases. Label and explain the main features of the variation. Homework Equations The Attempt at...

Homework Statement [/B] Okay guys I have attached a picture of my work. I guess my question really is, if they are telling me that Cp =7/2 am I allowed to assume that I am dealing with a diatomic gas? If so, that would change my equation to (5/2) instead of (3/2) correct? and therefore my...

I know Snell's Law and I do understand that there are single and multimode fibers. A fiber carries light hence to total internal reflection. so far so good. But is it only a single mode fibre that works with total internal reflection? And if so, how does the multimode fibre carry light then?

Homework Statement : [/B]Find the change in internal energy of 2kg water as it is heated from 0°C to 4°C. The specific heat capacity of water is 4200J/Kg and its densities at 0°C and 4°C are 999.9 kg/m3 and 1000kg/m3 respectively. Atm pressure=105PaHomework Equations :ΔU= Q-W W=PΔV M/V=D[/B]The...

Homework Statement Refer to image attached. Lets say I have a deformable solid that is being accelerated by a force that is equally distributed along the back face of the Main Body that is drawn in the picture. Attached to this Main Body is a Wing. At high accelerations, there will be inertial...

Homework Statement When an external resistor of resistance R 1 = 14 Ω is connected to the terminals of a battery, a current of 6.0 A flows through the resistor. When an external resistor of resistance R2 = 64.4 Ω is connected instead, the current is 2.0 A. Calculate the emf and the internal...

Homework Statement In this problem , it's a Internal Indeterminate truss . Homework EquationsThe Attempt at a Solution So , I remove one of the redundant member , AC and solve the problem . For the first part , I found the real force first . for the second part , I apply the virtual unit...

When a laser beam reflects during total internal reflection, how much of its intensity is lost? I can't the use Fresnel equations as this is for total internal reflection.If you don't know the answer to the above question, what about the same question, but for mirrors instead? What are the...

If we continue to draw a specific amount of power from a cell (re-chargable), how will the internal resistance of the cell vary? Is there any particular mathematical relation between them? Please help me understand

Homework Statement I am trying to understand the law of conservation of energy from a very general perspective but coming across some issues. I am using the equation mentioned at end of this post, which is true for a system with no heat flows into or out of the system. In two situations...

Just out of curiosity, as I am very amateur here, in ICE could mono-crystal Alumina replace aluminum and create a better engine? Aside from the high cost to manufacture. I know MC-Alumina has a higher density than Al but is considerably stronger. This would be fantastic, I would think for a...

Homework Statement I made an apparatus of a rectangular prism dangling from a vertical string from one side while the other is touching the ground. The relationship I'am trying to find is between the angle of the prism relative to the ground and the normal force exerted up wards. I am stuck on...

Homework Statement I need to calculate EMF and internal resistance from the given resistance and voltage. R = 3 ohms U = 3,6 V EMF- ? I0 - ? r - ? Homework Equations I = U/R EMF = A/q I = EMF/R+r I0 = EMF/r The Attempt at a Solution I = 3,6/3 = 1,2 A I = EMF/R+r 1,2= EMF/3+r ^ I hit a wall...

Dear Experts, Trying to analyze the work done by internal forces in a very simple two particle system which is attracted to each other with a constant force, i performed calculations based on two frame of references, 1.The center or mass frame of reference and 2. Frame of reference of one of the...

Homework Statement [/B] Calculate the internal resistance of V & A based on methods A & B below: Method A Voltmeter = 1.46 V Ammeter = 0.24 A E (emf of battery) = 1.48 V Method B Voltmeter = 1.48 V Ammeter = 0.24 A E (emf of battery) = 1.48 VHomework Equations Ohm's Law: V = I*R The...

Homework Statement A closed, rigid tank contains 2 kg of water, initially a two phase liquid–vapor mixture at T1 = 70°C. Heat transfer occurs until the tank contains only saturated vapor at T2 = 120C. Determine the heat transfer for the process, in kJ. answer choices: 3701kJ 119.4kJ 4835kJ...

Homework Statement Water is initially at P = 1 bar and T = 20°C. 100kg of water is pumped to a higher pressure at which P = 10 bar and T = 25°C. Find ΔU and ΔH Homework Equations H = m*h du = c*dT dh = c*dT + v*dP The Attempt at a Solution So far I have looked in my table and found that at P...

Homework Statement CO2 is at P=3atm, T = 295K and V=1.2m3. It is isobarically heated to T = 500K. Find ΔU and ΔH Homework Equations dU = cpdT The Attempt at a Solution I am having a hard time in general in this class. I understand that in this problem, ΔP = 0. Does this mean that there must...

Let V be a vector space. If U 1 and U2 are subspaces of V s.t. U1+U2 = V and U1 and U1∩U2 = {0V}, then we say that V is the internal direct sum of U1 and U2. In this case we write V = U1⊕U2. Show that V is internal direct sum of U1 and U2if and only if every vector in V may be written uniquely...

Hello everybody, My question today is: Given a molecule that has an internal degree of liberty ( let's take the ethane molecule with its internal rotation as an example), how to write the kinetic energy operator by means of the corresponding internal coordinate? Thank you guys. Konte

According to the first law of thermodynamics, dQ = dU + dW and you can find dU = nCvdT If this is the case then when water at 100°C vaporizes to steam at 100°C shouldn't the change in internal energy be zero because it is dependent on temperature change?

It is known that wavefronts of internal OAM photons travel slower than light but I wonder what happens if you accelerate such a beam. This should be possible under gravity.

Hi , How can I calculate the resistive heating occurring in the internal resistances of a solar cell ? Are ohm's law or the power dissipation relation P=RI2 applicable in this case ? if not the case how can we calculate the resistive heating there? Thank you in advance for your help

Homework Statement In that pin configuration, what does the triangle and rectangle in the middle represent?

Homework Statement For this problem , i found that the internal force AB at point A and point B pointed in the same direction ( as shown) in my working , so , how they cancel off each other ?Since they can't cancel off each other , so they are not stable , right ? The structure is statically...

Hi, how to predict indoor temperature with or without HVAC? I have the internal temperature's value, the external temperature's value and the temperature of HVAC's air output. I want two function, one with HVAC on and other with mode off. Hp: start time 0, end time Tend. Tend has values from 0...

Homework Statement : [/B]At the beginning of the compression stroke of a two-cylinder internal combustion engine the air is at a pressure of 101.325 kPa. Compression redeuces the volume to 1/5 of its original volume, and the law of compression is given by PV^1.2 = const. If the bore and stroke...

Homework Statement What is the change in internal energy (in Joules) of an ideal gas that does 4.675x10^5J of work, while 2.95x10^6J of heat is transferred into the system and 7.95x10^6J of heat is transferred from the system to the environment? Calculate the change in temperature of the two...

Homework Statement We are asked to derive the expression for the internal energy of an ideal Fermi degenerate gas using Sommerfeld expansions, writing out terms up to the fourth order in ##(\frac{T}{T_F} )## , that is, we must determine ## \alpha ## in the following expression: $$ U=...

I've been given the following relations where as I understand it subindex 2 equals subindex e and subindex 1 equals subindex i: ***EDIT*** More accurately subindex 1; initial state of a control mass subindex 2: end state of a control mass (end state is simply state 2 in the problem at hand)...

Homework Statement Below, two experiments (1 and 2) are described, in which the same quantity of solid carbon dioxide is completely sublimated, at 25ºC: The process is carried out in a hermetically sealed container, non-deformable with rigid walls; The process is carried out in a cilinder...

Homework Statement I am working on a thin film interference problem where i have to find the phase difference. What is the relationship between external/internal reflection and the thin film interferenceHomework Equations for external: [/B] for internal: The Attempt at a Solution So far i...

Homework Statement Homework EquationsThe Attempt at a Solution https://scontent-kul1-1.xx.fbcdn.net/v/t35.0-12/15146781_1334186669946177_363846788_o.jpg?oh=b75be99f63eba2e70db5e0287581076b&oe=583538C2 The answer given by the book is " Reflection ". But why isn't it Total Internal Reflection ?

Wick's theorem allows one to write a free theory time-ordered ##n##-point correlation function as a product of free theory time-ordered ##2##-point correlation function. The procedure involves the pairwise Wick contraction of fields such that external fields are not paired up each...

This table is given in my book, $$\begin{array}[c!c!c!c!] \text{ }&\text{ Transitional }&\text{ Rotational }& \text{ Vibrational} \\ \hline \text{Linear molecules} & 3&2& 3N -5\\ \hline \text{Non-Linear molecules} & 3&3& 3N -6\\ \hline \end{array}$$ It is also given...

Homework Statement Hi , I'm struggling with new paragraph about internal engines. When four-stroke internal combustion engine spins crankshaft 100 times , piston does 300 ticks. How many cilinders does engine has? Homework Equations I don't know how to create equation to calculate that , i...

I am looking over the kinetic theory of gases. It is most commonly described as U = (3/2)*N*k*T = (3/2)*mass*R*T for a monatomic gas, assuming the gas is ideal. This is based on the derivation, where ultimately (3/2)*P*V = N*K = total kinetic energy of particles. My question, for a real gas...

Hi, As is commonly known, u = u(T,v) h = u(T,p) I've worked with some maths proofs of this a while ago, but do you guys have an intuitive way of understanding this without the maths, that is, why the state function for internal energy is defined by intensive volume and enthalpy with pressure...

I was wondering how they managed to know the internal structure of Earth and it's composition while there is lava and it's very hot such that no any instruments can get there...seriously I am confused

Homework Statement [/B] A nail is heated in a bunsen burner flame and is about to be dropped into a beaker of water at room temperature. a) Which of the two substances (nail or water) would you expect to initially have: i) the highest internal energy ii) the highest average kinetic...

We know, $$dU=TdS-PdV$$ ##\int PdV## can be calculated if the equation of state is given. I tried to express ##S## as a function of ##P ,V## or ##T## (any two of those). $$dS=\left(\frac{\partial S}{\partial V}\right)_T dV+\left(\frac{\partial S}{\partial T}\right)_V dT$$ $$=\left(\frac{\partial...

Homework Statement A bulb is used in a torch which is powered by two identical cells in series each of EMF 1.5 V. The bulb then dissipates power at the rate of 625 mW and the PD across the bulb is 2.5 V. Calculate (i) the internal reistance of each cell and (ii) the energy dissipated in each...

Homework Statement The battery in the circuit below has EMF 5.4 V and drives a current of 0.30 A through a lamp. The voltmeter reading is 4.8 V. Explain why the voltmeter reading is less than the EMF of the cell. Calculate values for (a) the internal resistance of the battery, and (b) the...

Homework Statement A uranium-238 atom can break up into a thorium-234 atom and a particle called an alpha particle, α-4. The numbers indicate the inertias of the atoms and the alpha particle in atomic mass units (1 amu = 1.66 × 10−27 kg). When an uranium atom initially at rest breaks up, the...

Homework Statement I need to describe an experiment in which I would use internal reflection to determine the index of refraction of material Homework Equations Snell's law The Attempt at a Solution I understand the concept of internal reflection, such as the critical angle etc. I am just...

Homework Statement There is a monatomic gas held at a constant pressure of P = 1.48-atm, it also has a molar mass M = 16-g/mol and density ρ =1.9 × 10-3-g·cm-3. Find the total internal energy of 1-mol of this gas. Homework Equations U = Q + W E = nCvT PV = nRT The Attempt at a Solution I...

Homework Statement A cylinder contains 0.250mol of carbon dioxide (CO2) gas at a temperature of 27.0∘C. The cylinder is provided with a frictionless piston, which maintains a constant pressure of 1.00atm on the gas. The gas is heated until its temperature increases to 127.0∘C. Assume that the...

A gas in a cylinder with constant pressure, the gas cooled down and its internal energy decreased as well as its volume. The heat Q will be flowing into the gas or out of the gas? My try for the solution: As the volume decrease the work done by the gas will be negative. The gas cooled down, so...

Hello, I know that the sensory cortex in the postcentral gyrus collects sensory information from different parts of the body, but in all the drawings and explanations, I see that it only gathers information from the surface of the body. Which part of the brain gathers information from our...