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Physics · Textbook solutions

Thermodynamics

Every solved example, exercise, and miscellaneous question — in the order the textbook teaches them. · 14 questions

Exercises

14 q
  1. Ex 11.1
    A geyser heats water flowing at the rate of 3.0 litres per minute from 27 ∘C27\,^\circ\text{C} to 77 ∘C77\,^\circ\text{C}. If the geyser operates on a gas burner, what is the rate of consumption of the fuel if its heat of combustion is 4.0×104 J/g4.0 \times 10^{4}\,\text{J/g}?
  2. Ex 11.2
    What amount of heat must be supplied to 2.0×10−2 kg2.0 \times 10^{-2}\,\text{kg} of nitrogen (at room temperature) to raise its temperature by 45 ∘C45\,^\circ\text{C} at constant pressure? (Molecular mass of N2=28\text{N}_2 = 28; R=8.3 J mol−1 K−1R = 8.3\,\text{J mol}^{-1}\,\text{K}^{-1}.)
  3. Ex 11.3(a)
    Explain why (a) Two bodies at different temperatures T1T_1 and T2T_2 if brought in thermal contact do not necessarily settle to the mean temperature (T1+T2)/2(T_1 + T_2)/2.
  4. Ex 11.3(b)
    Explain why (b) The coolant in a chemical or a nuclear plant (i.e., the liquid used to prevent the different parts of a plant from getting too hot) should have high specific heat.
  5. Ex 11.3(c)
    Explain why (c) Air pressure in a car tyre increases during driving.
  6. Ex 11.3(d)
    Explain why (d) The climate of a harbour town is more temperate than that of a town in a desert at the same latitude.
  7. Ex 11.4
    A cylinder with a movable piston contains 3 moles of hydrogen at standard temperature and pressure. The walls of the cylinder are made of a heat insulator, and the piston is insulated by having a pile of sand on it. By what factor does the pressure of the gas increase if the gas is compressed to half its original volume?
  8. Ex 11.5
    In changing the state of a gas adiabatically from an equilibrium state AA to another equilibrium state BB, an amount of work equal to 22.3 J22.3\,\text{J} is done on the system. If the gas is taken from state AA to BB via a process in which the net heat absorbed by the system is 9.35 cal9.35\,\text{cal}, how much is the net work done by the system in the latter case? (Take 1 cal=4.19 J1\,\text{cal} = 4.19\,\text{J})
  9. Ex 11.6(a)
    Two cylinders AA and BB of equal capacity are connected to each other via a stopcock. AA contains a gas at standard temperature and pressure. BB is completely evacuated. The entire system is thermally insulated. The stopcock is suddenly opened. Answer the following: (a) What is the final pressure of the gas in AA and BB?
  10. Ex 11.6(b)
    Two cylinders AA and BB of equal capacity are connected to each other via a stopcock. AA contains a gas at standard temperature and pressure. BB is completely evacuated. The entire system is thermally insulated. The stopcock is suddenly opened. Answer the following: (b) What is the change in internal energy of the gas?
  11. Ex 11.6(c)
    Two cylinders AA and BB of equal capacity are connected to each other via a stopcock. AA contains a gas at standard temperature and pressure. BB is completely evacuated. The entire system is thermally insulated. The stopcock is suddenly opened. Answer the following: (c) What is the change in the temperature of the gas?
  12. Ex 11.6(d)
    Two cylinders AA and BB of equal capacity are connected to each other via a stopcock. AA contains a gas at standard temperature and pressure. BB is completely evacuated. The entire system is thermally insulated. The stopcock is suddenly opened. Answer the following: (d) Do the intermediate states of the system (before settling to the final equilibrium state) lie on its PP-VV-TT surface?
  13. Ex 11.7
    An electric heater supplies heat to a system at a rate of 100 W100\,\text{W}. If system performs work at a rate of 75 joules per second. At what rate is the internal energy increasing?
  14. Ex 11.8
    A thermodynamic system is taken from an original state to an intermediate state by the linear process shown in Fig. (11.13) Its volume is then reduced to the original value from EE to FF by an isobaric process. Calculate the total work done by the gas from DD to EE to FF