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Engineering
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"Heat cannot by itself flow from a body at lower temperature to a body at higher temperature" is a statement or consequence of

  • Option 1)

    second law of thermodynamics

  • Option 2)

    conservation of momentum

  • Option 3)

    conservation of mass

  • Option 4)

    first law of thermodynamics.

 
As we learnt in Second Law of Thermodynamics - Clausius Statement - wherein Heat cannot flow from a cold body to a hot body without the performance of work by some external agency.   This statement comes naturally from the second law of thermodynamics. Heat can only flow from the body at lower temperature to a body at higher temperautre when we do work on the body.   Option 1) second law of...
Engineering
346 Views   |  

Which of the following parameters does not characterize the thermodynamic state of matter?

  • Option 1)

    temperature

  • Option 2)

    pressure

  • Option 3)

    work

  • Option 4)

    volume

 
As we learnt in  Equation of state - The relation between the  Thermodynamics variable (P, V, T) of the system is called equation of state. - wherein    (P, V, T) represent Thermodynamic state of matter. Work does not represent thermodynamic state of matter. Option 1) temperature This option is incorrect. Option 2) pressure This option is incorrect. Option 3) work This option is...
Engineering
266 Views   |  

A Carnot engine takes 3\times 10^{6}  cal  of heat from a reservoir at 627^{\circ}C,  and gives it to a sink at 27^{\circ}C.  The work done by the engine is

  • Option 1)

    4.2\times 10^{6}\, J

  • Option 2)

    8.4\times 10^{6}\, J

  • Option 3)

    16.8\times 10^{6}\, J

  • Option 4)

    zero

 
As we learnt in  Efficiency of a cyclic process -   - wherein Gross heat implied only part of heat absorbed.     Efficiency of a carnot cycle -   are in kelvin   - wherein Source temperature Sink Temperature    Given,   or  or    Option 1) This option is incorrect. Option 2) This option is correct. Option 3) This option is incorrect. Option 4) zero This option is incorrect.
Engineering
116 Views   |  

During an adiabatic process, the pressure of a gas is found to be proportional to the cube of its absolute temperature. The ratio C_{P}/C_{V} for the gas is

  • Option 1)

    4/3\;

  • Option 2)

    \; 2\;

  • Option 3)

    \; 5/3\;

  • Option 4)

    \; 3/2

 
As we learnt in Equation of state -   - wherein On solving   In the given question or  = constant ......(1)  From adiabatic equation .....(2) From equation 1 and 2   Option 1) The option is incorrect. Option 2) The option is incorrect. Option 3) The option is incorrect. Option 4) The option is correct.
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