What is Energy calculation: Definition and 49 Discussions
In thermodynamics, the Gibbs free energy (or Gibbs energy) is a thermodynamic potential that can be used to calculate the maximum reversible work that may be performed by a thermodynamic system at a constant temperature and pressure. The Gibbs free energy (
Δ
G
=
Δ
H
−
T
Δ
S
{\displaystyle \Delta G=\Delta H-T\Delta S}
, measured in joules in SI) is the maximum amount of non-expansion work that can be extracted from a thermodynamically closed system (one that can exchange heat and work with its surroundings, but not matter). This maximum can be attained only in a completely reversible process. When a system transforms reversibly from an initial state to a final state, the decrease in Gibbs free energy equals the work done by the system to its surroundings, minus the work of the pressure forces.The Gibbs energy (symbol
G
{\displaystyle G}
) is also the thermodynamic potential that is minimized when a system reaches chemical equilibrium at constant pressure and temperature. Its derivative with respect to the reaction coordinate of the system vanishes at the equilibrium point. As such, a reduction in
G
{\displaystyle G}
is necessary for a reaction to be spontaneous at constant pressure and temperature.
The Gibbs free energy, originally called available energy, was developed in the 1870s by the American scientist Josiah Willard Gibbs. In 1873, Gibbs described this "available energy" as
the greatest amount of mechanical work which can be obtained from a given quantity of a certain substance in a given initial state, without increasing its total volume or allowing heat to pass to or from external bodies, except such as at the close of the processes are left in their initial condition.
The initial state of the body, according to Gibbs, is supposed to be such that "the body can be made to pass from it to states of dissipated energy by reversible processes". In his 1876 magnum opus On the Equilibrium of Heterogeneous Substances, a graphical analysis of multi-phase chemical systems, he engaged his thoughts on chemical-free energy in full.
If the reactants and products are all in their thermodynamic standard states, then the defining equation is written as
## \ \ \ \ \ ##In ##K##，System ##M## is composed of a spring ## N ## and four particles ## P, Q, A and B ##. The ends of spring ## N ## are fixedly connected with particles ## P and Q ## respectively. Particle ## A ## is adjacent to particle ## P ##, and particle ## B ## is adjacent to particle...
Homework Statement
In Parseval's theorm, energy equals integral x(t) squre when x(t) represents voltage.
I wonder if x(t) represernts power, then does integral x(t) dt equal energy?? Because 'power multiplied time' means energy.
Homework Equations
The Attempt at a Solution
Since E = mc2 the if I know the mass and the energy I can figure out the constant c2, but how do I know how much energy does the body have ? How do I calculate it ?
Hello, can someone tell me how, or provide me a formula, to calculate the power of the turning shaft? in Nm or Watts, I don't mind. The mass (23Kgr) is turning at stable speed of 100 rpm by external independent force. The shaft is supposed to be on bearings both sides..
I made a picture to save...
Hi everyone.
Given: an asteroid with the mass of 50,000,000 kg, which is moving with the velocity of oh-my-god particle -- 99.99999999999999999999951% of c.
Due to relativistic effects, its total kinetic energy will be 1.44 E+36 Joules (Lorentz factor = 3.2 E+11).
A hypothetical particle...
Homework Statement
Homework Equations
No equations used (to my knowledge). Just arithmetic and understanding of what is being asked.
The Attempt at a Solution
Was wondering if my solution/approach to this question is correct or not? I don't have any answers to compare it to so any...
Homework Statement
Homework EquationsThe Attempt at a Solution
I didnt understand much the question. Should I use, ##υ=εE^2## ? Then I ll take rms value of that E.But I am not sure that is that the max value.Is it max value ? I didnt understand part (B)
Hello,
I used the Darcy Friction Factor from the Moody Diagram along with the Reynolds number to find energy losses inside the cold air tubing of our vortex system. My calculations showed that I should decrease transitions, length, diameter, and velocity. I am mainly concerned with the figuring...
Based on Laws of Physics, how to calculate the calories burnt by a person, weighing 60 kg during walking at a speed of 4 kmh–1 for 1 hour.
Surprisingly different answers were given by online calculators. Though I am not a Physicist, please let me know the formula or principle behind the...
Hi All,
First time poster here, and I've got a couple questions. Straight up, I'm writing a sci-fi story where antimatter is utilised as fuel (feel free to laugh at the cliche), and I want to portray it as realistically as possible. To that end, I've come up with a storage method and I want to...
Hi everyone!
I am trying to create a crude electron-hopping model to study conductivity in a biological wire composed of discrete sites. The model is pretty simple: imagine a line composed of sites. Electrons can hop from site to site with probabilities that depend on the free energy difference...
Hi there,
I am currently working for fun project and will like to know if anybody out there could help us with some calculations on how much energy its needed to fly different spaceships, please get in touch if you are interested in participating in the project.
Homework Statement
Given the scheme
https://www.dropbox.com/s/nm943gleo2nc8ft/Screenshot%202016-08-28%2013.47.33.png?dl=0
Springs' constant k=40 N\m
mass of bulk m=6kg
The wooden bulk is released at rest when all the springs are not stretched
Question: What is the elastic total maximal Energy...
Homework Statement
The longest homerun hit by Miguel Cabrera in the 2012 season occurred at Comerica Park and had an initial y-component of velocity of 19.8 m/s and an initial x-component of velocity given as m/s, where is some value left undetermined.
Assume the ball left the bat 1.22 m off...
Homework Statement
This is a Lab:
A Ball is placed on a 14cm high ramp and it rolls down to the bottom of the ramp and onto a table where it rolls 20cm (the ramp's horizontal displacement is 16.5cm). After rolling on the table, the ball falls off the table for 76.5cm with a forward horizontal...
When the calculation for the cohesive energy in a molecular solid is carried on, there appears a summation for the interaction of all the molecules or atoms in the solid, (see for example Kittel Introduction to solid state Physics 3rd edition, page 87). For noble gases, this interaction could be...
How to verify the Energy and Capacity delivered by the Lithium Ion battery?
I have a Lithium ion batter with below configuration:
Nominal Voltage 4.2 V
Nominal capacity 2250 mAh
I am calculating the energy and capacity every second for my experiments.
I use below formula to calculate the...
ΔG=ΔH-TΔSsystem and ΔSsystem=qp/T and isn't qp=ΔH? Which means ΔG=0 always which is obviously wrong.
But the derivation for Gibbs Free Energy is based on qsurrounding=-qsystem so shouldn't the term be equals to 0?
I hope this is the right place for this...
Question #1. How much can the human body stand multiple rapid G-force changes. Like let's say I made a vehicle that you could make sure all your body parts were 100% secured and it could move freely in space in any direction what would be the result of...
Hello
why we use cosine and sine in simple harmonic motion?
why we use particularly cosine with potential energy and sine with kinetic energy of simple harmonic oscillator?
regards
I've been asked to approximate a dollar amount for heating and cooling an occupied tenant space in a commercial office building.
We've looked into installing a temporary gauge on each unit to give us a good approximation, but the cost to gauge up all the electrical and gas was beyond the scope...
Homework Statement
A car of mass 850 kg is driven at a steady speed of 70 km/hr up a hilly road
with a slope of 30°. Using the macroscopic energy equation, determine the
power delivered by the engine of the car.
Homework Equations
E= KE + PE
E = (1/2)mC^(2) + mgz
Power = E/t...
Hi,
I'm trying to calculate theoretical energy generated by a system and I'm not sure if I'm doing it right and if I understand the concept properly. Here is my thinking, any input is appreciated.
12 billion joules of energy generated over 1800 seconds
equals roughly 6.8 million watts...
Hello everyone,
I am currently working on a classical MC simulation of helimagnets and I try to calculate the experimentally measured phase diagram.
Up to now I am able to reproduce a large piece of the phase diagram by using a single site Metropolis update and simulated annealing...
If a metal sphere that weights 1.006 kg is dropped from 2.5 meters, what is it's kinetic energy when it hits the ground?
Is this kinetic energy the same value as mechanical energy?
If this kinetic energy was converted in electrical energy by a 1000 watt electric generator that was 95%...
Greetings,
I have a work requirement to calculate building chilled water use based on known supply temp (deg F), return temp (deg F) and flow (GPM). I would like to know the relative error associated with the energy calculation. Based on the product data for the sensing equipment, I know that...
Greetings,
I have a work requirement to calculate building chilled water use based on known supply temp (deg F), return temp (deg F) and flow (GPM). I would like to know the relative error associated with the energy calculation. Based on the product data for the sensing equipment, I know...
Can we calculate the daily energy generation of 20KW power pack if have the following information:
Date Time GHI DNI DHI
01-01-2008 08:00 0 0 0
01-01-2008 09:00 149 398 75
01-01-2008 10:00 348 686 98
01-01-2008 11:00 512 792 112
01-01-2008 12:00 626 845 119...
Hi guys!
I searchead a lot for this but i couldn't find in anywhere: what calculation is made to esimate the vacuum energy of a scalar field??
I red that it starts considering the Hamiltonian in the form
\hat H=\frac{1}{2}\int d^{n-1}k[\hat n_k+\frac{1}{2}\delta^{n-1}(0)]\omega
and...
Homework Statement
suppose you had to carry ten 30lb concrete blocks up a 24ft ladder, to build a chimney. if you were paid for the work that you did on the blocks at the same price as electrical energy costs (14 cent kWh). how much money would you make from this job.
Homework Equations...
My friend asked me what does a 540 MW power plant mean and how to interpret,
I said it can lift a 1 Kilo Ton object to a height of 1 KM in about 3 Mins. My calculation is based on the equation of potential energy to the time taken by the power plant to produce that energy.
Is this the...
Homework Statement
A pipe end stop fails when subjected to high pressure and flys of the pipe before impacting with a polycarbonate protective screen.
The end stop has a mass of 100g and is 12.7mm dia. as is the internal diameter of the pipe. The instantaneous pressure that the end stop fails...
Hello,
I'd appreciate feedback on my calculation of binding energy, just wanted to check if I'm on the right track w/ regards to calculation steps (and thought process).
I'll try to be as clear as possible, please give me input if there's some notations / steps I should correct and keep...
Homework Statement
We must calculate the Fermi energy of metallic potassium at 0K. We have aleady found the number of atoms per m cubed, we are told that each atom contributes one electron to the free electron gas.
Homework Equations
Fermi energy = ((hbar^2)/2m)(((3Pi^2)N)/V)^3/2
The...
Energy Calculation ~~help
Homework Statement
Question )
An 800W electric motor is used to raise a load. In 120s, the load gains
24,000 J of gravitational potential energy from the motor
Calculate :
a) electrical energy supplied to the motor
b) energy wasted by the motor
c) output...
Hi everyone!
I am having a bit of a problem solving the following question (not good with maths), and would be very grateful for any advice given.
Homework Statement
A car is run for 400 hours per year, with a total mileage of 10,000 a year. The car uses diesel and consumes 2,000...
Homework Statement
When a spring fixed at one end is pulled by a force of 8N, the extension is 40mm. Two such springs are joined in series and is pulled to produce a total extension of 40mm. What is the strain energy in the springs.Homework Equations
strain energy, U = Fe / 2 or...
In the LHC, protons are accelerated to 99.9999991% of lightspeed. So gamma ~7500. At gamma of 7500, the energy content of proton is 7 TeV. So two colliding protons together should have a total mass-energy equivalentof 14 TeV.
Now, I want to calculate the total energy differently. The...
A 215 g particle is released from rest at point A inside a smooth hemispherical bowl of radius 30.0 cm. Point B to C have Height= 2/3(R)
Calculate the following: A. The gravitational potential energy at A relative to B
B. The particle's kinetic energy at B...
Hi there,
As part of my A2 physics coursework, i need to calculate the energy received by a water-antifreeze solution.
Basic setup: Lamp with 40W light bulb at a distance of 5cm away from an aluminium canister, which is filled with 100ml of water-glycol solution (at different...
Hi, I am new to this forum and wondering if anybody would be kind enough to help me.
A solar panel of area 2 m2 absorbs solar energy at the rate of
950 W/m2. Assuming that all the energy is used to heat water
in a 110 litre tank how long would it take for the water
temperature to...
Hello all,
I apologize if this is posted in the incorrect forum. I started working on a summer research project today and it is a part of the STAR experiment. Well, I am a fourth year undergrad (though I am slow by one year) and I am really in over my head here. The professor gave me an...
Homework Statement
A boy of 60 kgtakes 5 s to run up the slope in the diagram. (Please refer to the attachment) What is his average kinetic energy?
Homework Equations
The Attempt at a Solution
I don't know the meaning of 'average' kinetic energy. Is this mean kinetic energy per...
Hi
This seems like a helpful community so I thought I could ask you guys for some help.
First of all I need to clarify that English is not my first language so you'll have to excuse me if I make any grammatical or spelling errors.
Ok, here's my question:
I'm am trying to calculate...
I think the solution manual is wrong for this problem.
The problem:
The naturally occurring sugar glucose exists in two isomeric cyclic forms. These are called [alpha] and [beta], and at equilibrium they are present in a ratio of approximately 64:36. Calculate the free energy difference that...
A UV photon can break chemical bonds, but an IR photon can only cause vibration in the bonds. Calculate the energy associated with these processes by assuming a wavelength of 320 nm for the UV photon and a wavelength of 5000 nm for the IR photon.
I got...
UV photon: E = 6.22 x 10-19Joules...