Description : What happens in a reversible adiabatic compression? (A) Heating occurs (B) Cooling occurs (C) Pressure is constant (D) Temperature is constant
Last Answer : A) Heating occurs
Description : Pick out the wrong statement: (A) The expansion of a gas in vacuum is an irreversible process (B) An isometric process is a constant pressure process (C) Entropy change for a reversible adiabatic process is zero (D) Free energy change for a spontaneous process is negative
Last Answer : (B) An isometric process is a constant pressure process
Description : When the expansion of compression of gas takes place without transfer of heat to or from the gas the process is called a. reversible b. adiabatic c. polytropic d. isothermal
Last Answer : adiabatic
Description : The expression, ∆G = nRT. ln(P2/P1), gives the free energy change (A) With pressure changes at constant temperature (B) Under reversible isothermal volume change (C) During heating of an ideal gas (D) During cooling of an ideal gas
Last Answer : (A) With pressure changes at constant temperature
Description : Which of the following processes are thermodynamically reversible (a) throttling (b) free expansion (c) constant volume and constant pressure (d) hyperbolic and pV = C (e) isothermal and adiabatic.
Last Answer : Answer : e
Description : The expression for entropy change given by, ΔS = - nR ln (P2/P1), holds good for (A) Expansion of a real gas (B) Reversible isothermal volume change (C) Heating of an ideal gas (D) Cooling of a real gas
Last Answer : (B) Reversible isothermal volume change
Description : The expression for entropy change given by, ΔS = nR ln (V2/V1) + nCvln (T2/T1) is valid for (A) Reversible isothermal volume change (B) Heating of a substance (C) Cooling of a substance (D) Simultaneous heating and expansion of an ideal gas
Last Answer : (D) Simultaneous heating and expansion of an ideal gas
Description : Claude process of gas liquefaction employs (A) Merely compression of gas beyond its critical pressure (B) Joule-Thomson expansion cooling (C) Heat exchange with colder stream (D) Adiabatic expansion against a piston or in a turbine
Last Answer : (D) Adiabatic expansion against a piston or in a turbine
Description : The value of n = 1 in the polytropic process indicates it to be (a) reversible process (b) isothermal process (c) adiabatic process (d) irreversible process (e) free expansion process.
Last Answer : Answer : b
Description : Change in internal energy in a closed system is equal to heat transferred if the reversible process takes place at constant (a) pressure (b) temperature (c) volume (d) internal energy (e) entropy.
Last Answer : Answer : c
Description : Change in enthalpy in a closed system is equal to heat transferred if the reversible process takes place at constant (a) pressure (b) temperature (c) volume (d) internal energy (e) entropy.
Last Answer : Answer : a
Description : Adiabatic heating and Adiabatic cooling really means _________ and _________ respectively. a. raising the temp and lowering the temp b. maintaining the pressure and changing the temperature c. decreasing the volume and increasing the pressure d. lowering the temp and raising the temp
Last Answer : raising the temp and lowering the temp
Description : Adiabatic process is (A) Essentially an isentropic process is___________ (B) Non-heat transfer process (C) Reversible process (D) Constant temperature process
Last Answer : (B) Non-heat transfer process
Description : The adiabatic throttling process of a perfect gas is one of constant enthalpy (A) In which there is a temperature drop (B) Which is exemplified by a non-steady flow expansion (C) Which can be performed in a pipe with a constriction (D) In which there is an increase in temperature
Last Answer : (C) Which can be performed in a pipe with a constriction
Description : When the expansion of compression of gas takes place without transfer of heat or from the gas the process is called; a. Isometric process b. Isothermal process c. Isobaric process d. Adiabatic process
Last Answer : Adiabatic process
Description : Pick out the wrong statement (A) A horizontal line on the humidity chart indicates the temperature changes at constant molal humidity (B) When water is cooled from 80 to 70°C by exposure ... & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure
Last Answer : (D) Relative saturation of unsaturated mixture of water vapor & air cannot be increased by either reducing the mixture temperature or by increasing the total pressure
Description : Which of the following is not a reversible process? (A) Expansion of an ideal gas against constant pressure (B) Atmospheric pressure vaporisation of water at 100°C (C) Solution of NaCl in water at 50°C (D) None of these
Last Answer : C) Solution of NaCl in water at 50°C
Description : Which of the following is not correct for a reversible adiabatic process? (A) TV γ-1 = constant (B) p 1-γ .T Y = constant (C) PV γ = constant (D) None of these
Last Answer : (D) None of these
Description : In polytropic process (PV n = constant), if n = 1; it means a/an __________ process. (A) Adiabatic (B) Reversible (C) Isothermal (D) None of these
Last Answer : (C) Isothermal
Description : PVy = constant, holds good for an isentropic process, which is (A) Reversible and isothermal (B) Isothermal and irreversible (C) Reversible and adiabatic (D) Adiabatic and irreversible
Last Answer : C) Reversible and adiabatic
Description : In the equation, PVn = constant, if the value of n = ± ∞, then it represents a reversible __________ process. (A) Adiabatic (B) Isometric (C) Isentropic (D) Isothermal
Last Answer : (B) Isometric
Description : In the equation PVn = constant, if the value of n = y = Cp/Cv, then it represents a reversible __________ process. (A) Isothermal (B) Adiabatic (C) Isentropic (D) Polytropic
Last Answer : (C) Isentropic
Description : Pick out the wrong statement. (A) The net change in entropy in any reversible cycle is always zero (B) The entropy of the system as a whole in an irreversible process increases (C) The ... to a maximum (D) The entropy of a substance does not remain constant during a reversible adiabatic change
Last Answer : (D) The entropy of a substance does not remain constant during a reversible adiabatic change
Description : In the equation, PVn = constant, if the value of n = 1, then it represents a reversible __________ process. (A) Isothermal (B) Isobaric (C) Polytropic (D) Adiabatic
Last Answer : (A) Isothermal
Description : During adiabatic expansion of gas (A) Pressure remains constant (B) Pressure is increased (C) Temperature remains constant (D) None of these
Description : A process, in which the temperature of the working substance remains constant during its expansion or compression, is called A. isothermal process B. hyperbolic process C. adiabatic process D. polytropic process
Last Answer : Answer: A
Description : Air enters an adiabatic compressor at 300K. The exit temperature for a compression ratio of 3, assuming air to be an ideal gas (Y = Cp/Cv = 7/5) and the process to be reversible, is (A) 300 × (32/7) (B) 300 × (33/5) (C) 300 × (333/7) (D) 300 × (35/7)
Last Answer : A) 300 × (32/7)
Description : Claude gas liquefaction process employs cooling (A) At constant pressure (B) By throttling (C) By expansion in an engine (D) None of these
Last Answer : (C) By expansion in an engine
Description : Linde gas liquefaction process employs cooling (A) By throttling (B) By expansion in an engine (C) At constant pressure (D) None of these
Last Answer : (A) By throttling
Description : Claude's liquefaction process employs the cooling of gases by (A) Expansion in an engine (B) Following a constant pressure cycle (C) Throttling (D) None of these
Last Answer : A) Expansion in an engine
Description : __________ remains constant during the adiabatic cooling of moist air. (A) Wet bulb temperature (B) Dry bulb temperature (C) Relative humidity (D) Specific humidity
Last Answer : Option A
Description : Entropy of a substance remains constant during a/an __________ change. (A) Reversible isothermal (B) Irreversible isothermal (C) Reversible adiabatic (D) None of these
Last Answer : (C) Reversible adiabatic
Description : Adiabatic expansion resulting in cooling is called
Last Answer : Adiabatic expansion resulting in cooling is called A. coriolis effect B. joule-kelvin effect C. le chatelier principle D. principle of parsimony
Description : Consider the following processes: [IES-1999] 1. Constant pressure heat addition. 2. Adiabatic compression. 3. Adiabatic expansion. 4. Constant pressure heat rejection. The correct sequence of these processes in Rankine cycle is: (a) 1, 2, 3, 4 (b) 2, 1, 4, 3 (c) 2, 1, 3, 4 (d) 1, 2, 4, 3
Last Answer : (c) 2, 1, 3, 4
Description : During adiabatic, internally reversible process, what is true about the change in entropy? A. It is temperature-dependent B. It is always greater than zero C. It is always zero D. It is always less than zero
Last Answer : It is always zero
Description : Linde process of gas liquefaction employs (A) Exchange of heat with colder stream (B) Adiabatic expansion through a throttle valve (Joule-Thomson expansion) (C) Adiabatic expansion against a piston or in a turbine (D) Merely compressing the gas beyond its critical pressure
Last Answer : (B) Adiabatic expansion through a throttle valve (Joule-Thomson expansion)
Description : In case of an __________ process, the temperature of the system increases. (A) Isothermal compression (B) Isothermal expansion (C) Adiabatic expansion (D) Adiabatic compression
Last Answer : (D) Adiabatic compression
Description : The thermodynamic law, PVy = constant, is not applicable in case of (A) Ideal compression of air (B) Free expansion of an ideal gas (C) Adiabatic expansion of steam in a turbine (D) Adiabatic compression of a perfect gas
Last Answer : (B) Free expansion of an ideal gas
Description : The thermodynamic law, PVy = constant, is not followed by the (A) Free expansion of an ideal gas (B) Adiabatic expansion of steam in turbine (C) Adiabatic compression of air (D) Ideal compression of air
Description : When a gas in a vessel expands, its internal energy decreases. The process involved is (A) Reversible (B) Irreversible (C) Isothermal (D) Adiabatic
Last Answer : (A) Reversible
Description : Specific heat of a gas for a reversible adiabatic process is (A) Negative (B) Zero (C) Infinity (D) None of these
Last Answer : (B) Zero
Description : Entropy change in case of reversible adiabatic process is (A) Minimum (B) Zero (C) Maximum (D) Indeterminate
Description : The expression for the work done for a reversible polytropic process can be used to obtain the expression for work done for all processes, except reversible __________ process. (A) Isobaric (B) Isothermal (C) Adiabatic (D) None of these
Last Answer : (B) Isothermal
Description : Which of the following non-flow reversible compression processes require maximum work? (A) Adiabatic process (B) Isothermal process (C) Isobaric process (D) All require same work
Last Answer : (A) Adiabatic process
Description : Heating of water under atmospheric pressure is an __________ process. (A) Isochoric (B) Isobaric (C) Adiabatic (D) Isothermal
Last Answer : (B) Isobaric
Description : Isochoric process is one in which (a) free expansion takes place (b) very little mechanical work is done by the system (c) no mechanical work is done by the system (d) all parameters remain constant
Description : Which of the following processes is followed by unsaturated air (with dry bulb temperature 12°C and relative humidity 47%) passing through water spray washer (temperature of water being constant at 40°C ... (B) Heating only (C) Both heating and humidification (D) Evaporative cooling
Last Answer : (C) Both heating and humidification
Description : Which of the following psychrometric processes is followed by water vapour laden unsaturated air, when it is passed through solid or liquid adsorbent? (A) Cooling and dehumidification ... (C) Dehumidification with dry bulb temperature remaining constant (D) None of these
Last Answer : (B) Heating and dehumidification at almost constant wet bulb temperature
Description : In order that a cycle be reversible, following must be satisfied (a) free expansion or friction resisted expansion/compression process should not be encountered (b) when heat is being absorbed, temperature of hot ... sub-stance should be same (d) all of the above (e) none of the above.
Last Answer : Answer : d
Description : The effect that takes place which results in cooling action is1. Condensing 2. Heating 3. Cooling 4. Evaporating
Last Answer : Evaporating