Engineering Sciences
GATE XE topic:engineering PYQs
Build your understanding with focused practice from past exam papers.
Questions 1351–1360 of 1772. Imported answers require independent review unless marked reviewed.
Question 17
Open questionXE-ENAT2 marksNeeds review
In a vapor compression system, a refrigerant leaves the evaporator and enters the compressor in saturated vapor condition at 0°C. The specific enthalpies of the saturated liquid and the saturated vapor at 0°C are 50 kJ/kg and 250 kJ/kg, respectively. The refrigerant leaves the compressor with a specific enthalpy of 300 kJ/kg. From the exit of the condenser, the refrigerant is throttled to the evaporator pressure. If the coefficient of performance (COP) of the refrigerator is 2.8 then the dryness fraction of the refrigerant entering the evaporator is __________.
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 18
Open questionXE-ENAT2 marksNeeds review
Hot air, assumed as an ideal gas (cₚ = 1000 J/kg.K, γ = 1.4) enters a gas turbine at 10 bar, 1000 K and leaves at a pressure of 5 bar. Subsequently it expands in a nozzle to a pressure of 1 bar. Assume both these processes to be reversible and adiabatic. If the inlet velocity of the air to the nozzle is negligible, the final velocity (m/s, rounded off to 1 decimal place) of air at the exit of the nozzle is __________.
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 19
Open questionXE-ENAT2 marksNeeds review
The “
-
diagram” for a thermodynamic process is shown in the figure. The heat transferred (kJ/kg) during the reversible process 1-3 is __________.Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 20
Open questionXE-ENAT2 marksNeeds review
In a simple Rankine cycle, superheated steam enters the turbine at 100 bar, 500°C (h = 3375.1 kJ/kg, s = 6.5995 kJ/kg.K) at a rate of 1000 kg/s. It expands isentropically in the turbine to the condenser pressure. The temperature in the condenser is 30°C (h_f = 125.74 kJ/kg, s_f = 0.4368 kJ/kg.K, h_g = 2555.6 kJ/kg, s_g = 8.420 kJ/kg.K). Saturated water from the condenser is pumped back to the boiler. Neglecting the pump work, the efficiency (in percentage, rounded off to 1 decimal) of the cycle is __________.
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 21
Open questionXE-ENAT2 marksNeeds review
A rigid, adiabatic container has two parts (A) and (B) separated by a piston. Initially, part (A) is filled with 1 kg of an ideal gas (
J/kg.K,
J/kg.K) at 1 bar, 600 K. The part (B) is filled with 1 kg of the same ideal gas at 2 bar, 400 K. The piston is now removed. In the final state, the pressure (bar, rounded off to two decimal places) will be _____________.Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 22
Open questionXE-ENAT2 marksNeeds review
In a steady flow process, superheated steam at 70 bar and 450°C, is throttled to 30 bar in an insulated valve, at a rate of 2 kg/s. The changes in the kinetic energy and potential energy during the process are assumed to be zero. The rate of entropy generation (kJ/s.K rounded off to three decimal places) during the throttling process is _____________.
The thermodynamic property data for superheated steam at 70 bar and 450°C:
kJ/kg,
kJ/kg.K
The thermodynamic property data for superheated steam at 30 bar are given in the following table.T (°C) | h (kJ/kg) | s (kJ/kg.K) |
|---|---|---|
400 | 3231.7 | 6.9235 |
450 | 3344.9 | 7.0856 |
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 1
Open questionXE-FMCQ1 markNeeds review
The functionality of allyl alcohol (CH₂=CH-CH₂OH) for condensation reaction with terephthalic acid is
Your answerChoose one option.
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 2
Open questionXE-FMCQ1 markNeeds review
Which of the following polymers can be synthesized by ring opening polymerization?
Your answerChoose one option.
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 3
Open questionXE-FMCQ1 markNeeds review
The weather resistant polymer among the following is
Your answerChoose one option.
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answerQuestion 4
Open questionXE-FMCQ1 markNeeds review
If a combination of sodium and naphthalene is used to initiate polymerization of styrene, then the most likely mechanism of polymerization is
Your answerChoose one option.
Log in to check the answer
You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer