BARC 2021 ME: Subject Revision Quiz 1 for ESE & GATE ME Exams

Question 1

An inward flow reaction turbine has external & internal diameters of

&

, respectively. The velocity of flow through runner is constant & is equal to

. If the width of runner at inlet is 240 mm, then width at runner at outlet is more than inlet by ___.

Question 2

An ideal gas undergoes a constant temperature process in a closed system. The heat transfer and work respectively, are

Question 3

Water flows through a 0.8m diameter pipe at the end of which there is a reducer connecting to a 0.6 m diameter pipe. If gauge pressure at the entrance to reduce is 400 KN/m² and velocity is 2m/sec. Determine the magnitude of thrust on reducer(KN) assuming that frictional head loss through reducer is 1m.

Question 4

Two heat engines are connected in series in such a way that rejected heat of 1^st engine is directly feed to 2^nd engine. If the source temperature is 1600 K and sink temperature is 400 K. Then calculate intermediate temperature If both the engine produces the same work.

Question 5

Calculate the location of stagnation points if the velocity components in a 2D flow field are given as:

u = x+ y -3 ,
v = 2x – 4y +5

Question 6

Which of the following is true with relative to basic thermodynamics?

Question 7

Lawn sprinklers work on the principle of _________.

Question 8

Venturimeter is installed in a pipe of diameter 40 mm. If the throat diameter of venturimeter is 20 mm and the pressure difference between the pipe and throat section is found to be 120 kPa. Then neglecting the frictional losses, the water velocity in main pipe is (m/s)

Question 9

A certain amount of an ideal gas is initially at a pressure P₁ and temperature T₁. First, it undergoes a constant pressure process 1-2 such that T₂ = 3T₁/4. Then, it undergoes a constant volume process 2-3 such that T₃=T₂/2. The ratio of the final volume to the initial volume of the ideal gas is

Question 10

For the stability of a floating body the

Question 11

Two boilers one with superheater (h₁= 3200 KJ/Kg) and other without superheater (h₂ = 2800 KJ/Kg) are delivering equal quantities of steam into common main. What will be the enthalpy of common main?

Question 12

A rigid container of volume 0.6 m³ contains 1.0 Kg of water at 120⁰C (V_f = 0.00106 m³/Kg, V_g = 0.8908 m³/Kg). the states of water is

Question 13

Consider following statements:
I) A gas is said to be an ideal gas when intermolecular forces are zero.
II) A gas behaves as an ideal gas under high temperature and high pressure.
III For an ideal gas, the temperature variation w. r. t. pressure during throttling condition is zero.
IV) A gas cools during expansion only when the Joule Thomson coefficient is negative.
Which of the following statements is/are correct?

Question 14

For a reaction turbine the change of pressure energy inside the stator is

and the total change of energy inside is

. Then, the degree of reaction for the turbine is:

Question 15

A heat engine is supplied with 500 KW of heat at 800K heat rejection takes place at 400K. Which of the following results report a reversible cycle?

Question 16

The large vessel shown in the figure contains oil and water. A body is submerged at the interface of oil and water such that 45 percent of its volume is in oil while the rest is in water. The density of the body is ______kg/m³.
The specific gravity of oil is 0.7 and density of water is 1000 kg/m³.
Acceleration due to gravity g = 10 m/s².

Question 17

In a 0.18 m diameter, 250 m long horizontal pipe a lubricating oil of specific gravity 0.9 and dynamic viscosity 0.15 Pa-s is pumped at the rate of 0.04 m³/s. The power required to maintain the flow (in kW) is_______.

Question 18

A circular disc lies in the water such a way such that its axis perpendicular to its cross section and passing through the center is perpendicular to the free surface of water, then __________.

Question 19

What will be change in entropy of the system if a piston-cylinder arrangement contains 0.06 m³ of Nitrogen at 1bar and 295K is compressed isothermally until the pressure of the gas becomes 6 bar.

Question 20

The entropy of a gas at 1 bar and 298 K is 0. Find entropy change of the gas at 20 bar and 600K. The specific heat of the gas varies linearly with temperature.

C_p= (0.88+0.00029T) kJ/kgK and C_v = (0.57+0.00029T) kJ/kgK.