Q.1
One mole of an ideal gas at an initial temperature of T K does 6R joule of work adiabatically. If the ratio of specific heats of this gas at constant pressure and at constant volume is 5/3, the final temperature of gas will be
  • (T + 2.4) K
  • (T - 2.4) K
  • (T + 4) K
  • (T - 4) K
Q.2
In which process, the PV-indicator diagram is a straight line parallel to volume axis?
  • Isothermal
  • Isobaric
  • Irreversible
  • Adiabatic
Q.3
If the temperature of the source is increased, the efficiency of a Carnot engine?
  • Increases
  • Decreases
  • Remain constant
  • First increases and then remain constant
Q.4
An ideal gas A and a real gas B have their volumes increased from V to 2V under isothermal conditions . The increase in internal energy
  • Will be the same in both A and B
  • Will be zero in both the gases
  • Of B will be more than that of A
  • Of B will be more than that of A
Q.5
In a Carnot cycle, order of process is
  • isothermal expansion, adiabatic expansion and adiabatic compression
  • isothermal expansion, adiabatic compression and adiabatic expansion
  • adiabatic expansion, isothermal expansion and adiabatic compression
  • none of the above
Q.6
A diatomic ideal gas is compressed adiabatically to 1/32  of its initial volume. If the initial temperature of the gas is $T_i$ ( in kelvin)  and the final temperature is $pT_i$. The value of p is
  • 1
  • 2
  • 3
  • 4
Q.7
In a given process on an ideal gas, dW=0 and dQ
  • $\Delta T > 0$
  • $\Delta T < 0$
  • $\Delta T =0$
  • Insufficient information
Q.8
During adiabatic compression of a gas, its temperature
  • Falls
  • Remains constant
  • Rises
  • Becomes zero
Q.9
A given mass of a gas is compressed isothermally until its pressure is doubled. It is then allowed to expand adiabatically until its original volume is restored and its pressure is then found to be 0.75 of its initial pressure. The ratio of the specific heats of the gas is approximately
  • 1.20
  • 1.41
  • 1.67
  • 1.83
Q.10
“Heat cannot by itself flow from a body at a lower temperature to a body at higher temperature” is a statement of the consequence of
  • the second law of thermodynamics
  • conservation of momentum
  • conservation of mass
  • the first law of thermodynamics.
Q.11
In the following questions, a statement of assertion is followed by a statement of reason. You are required to choose the correct one out of the given four responses and mark it as (a) If both assertion and reason are true and reason is the correct explanation of the assertion. (b) If both assertion and reason are true but reason is not correct explanation of the assertion. (c) If assertion is true, but reason is false. (d) If both assertion and reason are false. (e) If reason is true but assertion is false Assertion: In an isolated system, the entropy increases Reason : The processes in an isolated system are adiabatic
  • (a)
  • (b)
  • (c)
  • (d)
  • (e)
Q.12
In the following questions, a statement of assertion is followed by a statement of reason. You are required to choose the correct one out of the given four responses and mark it as (a) If both assertion and reason are true and reason is the correct explanation of the assertion. (b) If both assertion and reason are true but reason is not correct explanation of the assertion. (c) If assertion is true, but reason is false. (d) If both assertion and reason are false. (e) If reason is true but assertion is false Assertion: The Carnot cycle is useful in understanding the performance of heat engines. Reason: The Carnot cycle provides a way of determining the maximum possible efficiency achievable with reservoirs of given temperatures  
  • (a)
  • (b)
  • (c)
  • (d)
  • (e)
Q.13
In the following questions, a statement of assertion is followed by a statement of reason. You are required to choose the correct one out of the given four responses and mark it as (a) If both assertion and reason are true and reason is the correct explanation of the assertion. (b) If both assertion and reason are true but reason is not correct explanation of the assertion. (c) If assertion is true, but reason is false. (d) If both assertion and reason are false. (e) If reason is true but assertion is false Assertion: Air quickly leaking out of a balloon becomes cooler. Reason: The leaking air undergoes adiabatic expansion.  
  • (a)
  • (b)
  • (c)
  • (d)
  • (e)
Q.14
In the following questions, a statement of assertion is followed by a statement of reason. You are required to choose the correct one out of the given four responses and mark it as| (a) If both assertion and reason are true and reason is the correct explanation of the assertion. (b) If both assertion and reason are true but reason is not correct explanation of the assertion. (c) If assertion is true, but reason is false. (d) If both assertion and reason are false. (e) If reason is true but assertion is false Assertion: The temperature of the surface of the sun is approx. 6000K. if we make a big lens and focus  the sun rays, we can produce a temperature of 8000K Reason: The higher temperature can be produced accordingly to the second law of thermodynamics
  • (a)
  • (b)
  • (c)
  • (d)
  • (e)
Q.15
An ideal gas having initial pressure P, volume V and temperature T is allowed to expand adiabatically until its volume becomes 5.66V while its temperature falls to T/How many degrees of freedom do the gas molecules have?
  • 5
  • 6
  • 7
  • 8
Q.16
Obtain the workdone by a gas dring the expansion as a function of the initial pressure P and Volume V
  • 3/2 PV
  • 5/4 PV
  • 1/2 PV
  • 3/4 PV
Q.17
A monotonic gas is taken through ABCDA cycle. A->B Constant Pressure process B->C Constant volume process C->D Constant Pressure process D->A Constant volume process The PV coordinates of point A are (P,V) The PV coordinates of point B are (P,3V) The PV coordinates of point C are (3P,3V) The PV coordinates of point D are (3P,V) then which of the following is not true
  • total work done in the cycle is -4V
  • Change in Internal energy =0
  • total work done in the cycle is 4V
  • Work done in Process CD=-6PV
Q.18
The first law of thermodynamics dU=dQ-dW,indicates that when a system goes from its initial state to a final state
  • dU is same for every path
  • dQ is same for every path
  • dQ+dW is same for every path
  • dQ-2dW is same for every path
Q.19
A gas is contained in a vertical, friction less piston cylinder device. The piston has a mass of 20 kg with a cross-sectional area of 20 cm2 and is pulled with a force of 100N. If the atmospheric pressure is 100 kPa, determine the pressure inside.
  • 110 kPa
  • 100kPa
  • 150kPa
  • 200 Kpa
Q.20
For an adiabatic process
  • $\Delta S=0$
  • $\Delta U=0$
  • Q =0
  • W=0
0 h : 0 m : 1 s