Application Of First Law Of Thermodynamics , Isobaric process , Graph Of Isobaric Process. Grap of isochoric process.

 Application Of First Law Of Thermodynamics :

There Are Six Application Of 1st Law Thermodynamics.

. Isobaric Process .

. Isochoric Process .

. IsoThermal  Process

. Adiabatic Process

. Therottiny process. 

Isobaric process :

The word isobaric cames from the greek word iso = same and baros = pressure. 

. The process in which pressure of system remains constant this is called isobaric. 

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. Consider the figure in which a system in closing an ideal gas is shown when an infinite simal amount of heat is suplied to a system then expansion taken place in it. 

. When the piston start moving then the internal pressure of gas molecules become equal external pressure of atmosphere and weight of piston.  The pressure at this point is said to be the constant .

. In this process the work done by the gas molecule is given by      .•. Δx  - p= f/A.  , F= P/A

                                    Δw = G. 

                                   Δw = PA

                                   Δw = PΔV

. Now by using the equation of the 1st law of thermodynamics we have. 

                                ΔQ = ΔU + ΔW

                               ΔQ = ΔU + PΔV ( for isobarics process). 

. In this process.

1). The amount of heat is absorbed by the system i. e  ΔQ is +ve. 

2). The internal energy of system increase i. e ΔU is +ve. 

3). The work done by the system i. e Δw is +ve.

Graph Of Isobaric Process. 

Graph of isobaric process is known as isobar. 

It is a stright line along the axis of volume. 

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Isochoric process .

The process in which the volume of system remain constant is called  isochoric

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Consider the given figure in which are ideal gas is inclosed in a specific system when an infinitesimal amount of heat is supplied to a system then expansion taken place in the gas molecule, but this expansion is prevented by putting the load over the piston. 

In this system. 

Δv = 0, Δx =0,  Δw=0.

. Now by using the equation of 1st law of thermodynamics we have. 

Δw=0, ΔQv = ΔU,  Qv= ncvΔT. 

ΔQ = ΔU + ΔW.    

ΔQ = ΔU. 

ΔU = nCΔT. 

In this process. 

i).  Rhe amount heat is absorb by the system i. e ΔQ is positive. 

ii).  In this process only the internal energy of system increase i. e ΔU is positive. 

. In this process the work done is zero. 

. In this process the pressure law is valid become of constant volume and pressure is directly proportional to temperature i. e 

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Grap of isochoric process. 

The graph of isochoric process is known iso-chor.

. It is a straight line drawn along the axis of pressure. 

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