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    Internal Energy

    Internal energy is the total energy contained by a thermodynamic system. It is the energy required to create the system but remove the energy to displace the system’s surroundings, any energy connected with a move as a whole. The internal energy of a system can be changed by heating or cooling the system. The first law of thermodynamics states that an increase in internal energy is equal to the total heat added and work done by the surroundings.Therefore if a system is isolated, the internal energy cannot change.

    Internal energy is a state function of a system because its value depends only on the current state of the system and not on the path taken or process underdone to arrive at the state. It is an extensive quantity. The SI unit of internal energy is a joule (J). Specific internal energy is the internal energy per unit of mass of the system in question.
    Internal energy can be calculated by:

    U= U_pot+ U_kin

    And the change in internal energy is

    ∆U=Q+ W_mech+ W_extra

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    BrainMass Categories within Internal Energy

    System Work

    Solutions: 44

    Work is the energy transferred by a system to another.

    First Law of Thermodynamics

    Solutions: 54

    The first law of thermodynamics states that the internal energy of an isolated system will remain constant and the energy cannot be destroyed.

    BrainMass Solutions Available for Instant Download

    Analysis of Internal Energy Changes, Catalysts and pH

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    Heat capacity and work done by various systems

    Questions: a. Calculate the heat capacity of a radiator coolant if a temperature rises from 5 to 107 °C requires 932 J of heat. b. What is the change in internal energy for a system that does 7.02 kJ of work and absorbs 888 J of heat?

    Entropy Change and Maximum Work Problem

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    Thermodynamics: Enthalpy Change

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    Waves and oscillations

    A sound source sends a sinusoidal sound wave of angular frequency 3000 rad / s and amplitude 12.0 nm through a tube of air. The internal radius of the tube is 2.00 cm. (a) What is the average rate at which mechanical energy is transported to the opposite end of the tube? If an identical wave and the original wave travel alon

    Helmholtz free energy problem

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    Determining Solutions for Example Physics Problems

    1. How many calories are needed to raise 500 grams of water from 25 degrees Celsius to 40 degrees Celsius? 2. Define the following terms: a. Internal energy b. Specific heat c. Entropy d. Temperature 3. Suppose a 1 meter long bar expands 0.5 centimeters when heated. By how much will a 100 meter long bar of the sam

    Thermal Physics Entropy

    An ideal gas has a specific heat given by Cv = A+BT, where A and b are constants. Show that the entropy per kilo-mole in going from state (v1,T1) to state (v2,T2) is: delta(s) = A ln (T2/T1)+ B(T2-T1)+ R ln (v2/v1).

    Heat capacity of a 2d electron gas and of a 2d phonon gas.

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    First law of thermodynamics

    Show that under certain conditions, that you should state, dQ = cp dt - V dp for unit mass of an ideal gas. (Please also see the attachment)

    Thermodynamic process problem

    A The drawing refers to one mole of a monatomic ideal gas and shows a process that has four steps, two isobaric (A to B, C to D) and two isochoric (B to C, D to A). Complete the following table by calculating U, W, and Q (including the algebraic signs) for each of the four steps and for the whole process.

    Heat and Thermodynamics: Monoatomic to diatomic

    Initially, a quantity of a mono atomic gas (cv=3R/2) occupies a rigid container with volume V=0.19m^3. The temperature and pressure are Ti=287k and Pi=108Kpa. The gas reacts completely with itself to form half the original moles of a diatomic gas (cp=5R/2). The reaction is exothermic and produces an amount of heat Q=36497 J whic

    Heat and Thermodynamics: Change in internal energy.

    A cylinder (cross section is 0.2m2) with a free moving piston is filled with gas. The piston is attached to a heavy weight W = 10000N. Outside the cylinder, the air is at 300K and 1 atm. Initially the gas is at 300K, then it is heated to 400K. The heat capacity of the gas under the constant pressure is 500J/K. If the length of

    Debye Model of Lattice Specific heat

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    Global Management

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    Heat and Thermodynamics:Entropy change in Isothermal process

    One mole of an ideal gas is contained in a thermally insulated container that is connected to another container of equal volume that is initially evacuated. The valve connecting the two containers is now opened and the gas allowed to expand isothermally to fill both sides - new total volume is twice original volume. A) What i

    application of work-energy theorem

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    Mixing of Liquids: Temperature and Energy

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    Energy and work done by a gas system

    An insulated cylinder closed at one end by a frictionless piston contains 20g of hydrogen gas at 30 degrees Celsius. This is heated to 40 degrees Celsius with the pressure kept constant at 1 bar and the volume increases by 7*10^-4 m^3. (The specific heat of H2 at constant pressure is 1.4*10^4 JKg^-1 K^-1). a) What is the wor

    Applying to Ideal Gas Equation

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    Change in internal energy

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    Canonical Ensemble

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