Applications of First Law of Thermodynamics

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Applications of First Law of Thermodynamics: Overview

This Topic covers sub-topics such as Work Done in Reversible Adiabatic Process, Graph of Adiabatic Process, Graph of Isobaric Process, Work Done in Irreversible Adiabatic Process, Graph of Isothermal Process and, Graph of Isochoric Process

Important Questions on Applications of First Law of Thermodynamics

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The work done during the expansion of a gas from a volume of 4dm3to6dm3against a constant external pressure of 3 atm is (1 L atm = 101.32 J):

                               

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3 moles of an ideal gas expands isothermally against a constant pressure of 2 Pascal from 20 L to 60 L.The amount of work involved is

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One mole of an ideal gas is taken from a and b along two paths denoted by the solid and the dashed lines as shown in the graph below. If the work done along the solid line path is ws and that along the dotted line path is wd, then the integer closest to the ratio wd/ws is:

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The change in internal energy equals

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The magnitude of reversible work done by an ideal gas in four different processes: isothermal expansion, adiabatic expansion, constant pressure expansion, and free expansion are Wi, Wa, Wp, and Wf respectively. Choose the right order of sequence for the magnitude of the work done. (Change in the volume is same for all the processes.)

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A thermodynamic cycle in the pressure P-volume V plane is given below:
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AB and CD are isothermal processes while BC and DA are adiabatic processes. The same cycle in the temperature T- entropy S plane is :

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One mole of an ideal gas (at 25°C ) is expanded from volume 1 L to 4 L at constant temperature. The value of work done (in J), if gas is expanded against vacuum Pext=0?

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Among the following, which expression is most accurate to calculate the work done by gas in reversible isothermal expansion?

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Adjacent figure shows the force-displacement graph of a moving body, the work done in displacing body from x=0m tox=35m by the shown force is equals to

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An ideal gas is taken around the cycle ABCA as:

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Calculate work done in the cyclic process?

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P-V plots for two gases during adiabatic expansion are shown in figure. Plots 1 and plots 2 should correspond respectively to

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Two moles of a gas expand reversibly and isothermally at temperature of 300K. Initial volume of the gas is 1L while the final pressure is 4.926 atm. The work done by gas is

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For an isothermal reversible expansion process, the value of q can be calculated by the expression

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Which of the following P-V diagram represent the graph of isochoric process?

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A system consisting of 1 mol of an ideal gas undergoes a reversible process, ABCA (schematically indicated in the figure below). If the temperature at the starting point A is 300 K and the work done in the process BC is 1 L atm, the heat exchanged in the entire process in L atm is

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For a certain process, the pressure of a diatomic gas varies according to the relation P = aV 2 , where a is a constant. The molar heat capacity of the gas for this reaction is.

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The slope of isothermal and adiabatic curves are related as

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Which of the figures given below show the adiabatic process?
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Assertion: Work done by a gas in reversible isothermal expansion is more than the work done by the gas in reversible adiabatic expansion if final volume is same.

Reason: Temperature remains constant in isothermal expansion, and not in adiabatic expansion.

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Calculate Q and w for the isothermal reversible expansion of one mole of an ideal gas from an initial pressure of 1.0 bar to a final pressure of 0.1 bar at a constant temperature of 273K.