Solved Gate Questions on Power Engineering
Question 1. A single acting two-stage compressor with complete intercooling delivers air at 16 bar. Assuming an intake state of 1 bar at 15
, the pressure ratio per stage is
(A) 16
(B) 8
(C) 4
(D) 2
GATE-ME-2001
Hint 1. (Ans C)
Question 2. The Rateau turbine belongs to the category of
(A) Pressure compounded turbine
(B) Reaction turbine
(C) Velocity compounded turbine
(D) Redial flow turbine
GATE-ME-2001
Hint 2. (Ans A)
Question 3. The efficiency of the super Rankine cycle is higher than that of simple Rankine cycle because
(A) The enthalpy of main steam is higher for superheat cycle
(B) The mean temperature of heat addition is higher for super heat cycle
(C) The temperature of steam in the condenser is high
(D) The quantity of the steam in the condenser is low
GATE-ME-2002
Hint 3. (Ans B)
Question 4. A correctly designed convergent-divergent nozzle working at a designed load is
(A) Always isentropic
(B) Always choked
(C) Never choked
(D) Never isentropic
GATE-ME-2002
Hint 4. (Ans B)
Question 5. In a gas turbine, hot combustion products with the specific heats, 
and 
, enters the turbine at 20 bar, 1500 K and exit at 1 bar. The isentropic efficiency of the turbine is 0.94. The work developed by the turbine per kg of gas flow is
(A) 689.64 KJ/Kg
(B) 794.66 KJ/Kg
(C) 1009.72 KJ/Kg
(D) 1312.00 KJ/Kg
GATE-ME-2003
Hint 5. (Ans A)
Given 
For process, 3-4s
Now turbine efficiency,
Now turbine work,
Question 6. Considering the variation of static pressure and absolute velocity in an impulse steam turbine, across one row of moving blades
(A) Both pressure and velocity decrease
(B) Pressure decreases but velocity increases
(C) Pressure remains constant, while velocity increases
(D) Pressure remains constant, while velocity decreases
GATE-ME-2003
Hint 6. (Ans D)
Question 7. In a Rankine cycle, regeneration results in higher efficiency because
(A) Pressure inside the boiler increases
(B) Heat is added before steam enters the low pressure turbine
(C) Average temperature of heat addition in the boiler increases
(D) Total work delivered by the turbine increases
GATE-ME-2003
Hint 7. (Ans C)
Answer keys
1. (C) 2. (A) 3. (B) 4. (B) 5. (A) 6. (D) 7. (C)