Engineering Thermodynamics (3131905) MCQs

MCQs of First Law of Thermodynamics

Showing 21 to 30 out of 38 Questions
21.

In a steady flow process, the rate of

(a)

heat transfer is constant

(b)

work transfer is constant

(c)

mass flow at inlet and outlet is same

(d)

all of these

Answer:

Option (d)

22.

Which of the following is true?

(a)

in a steady flow system, no work is done on the atmosphere

(b)

in case of unsteady flow system, the volume of the system changes

(c)

both of the mentioned

(d)

none of the mentioned

Answer:

Option (c)

23.

The first law of thermodynamics for closed system undergoing change of state is

(a)

Q=U-W

(b)

Q=U+W

(c)

Q=H+W

(d)

Q=H-W

Answer:

Option (b)

24.

The Steady Flow Energy Equation (SFEE) per unit mass is given by

(a)

h1+C122+z1g+q=h2+C222+z2g+w

(b)

h1+C122+z1+q=h2+C222+z2+w

(c)

u1+C122+z1+q=u2+C222+z2+w

(d)

all of these

Answer:

Option (a)

25.

The function of nozzle is

(a)

convert kinetic energy to pressure energy

(b)

convert pressure energy to kinetic energy

(c)

convert potential energy to kinetic energy

(d)

convert kinetic energy to potential energy

Answer:

Option (b)

26.

The SFEE for nozzle is

(a)

C2=2h1-h2-C12

(b)

C2=2h1-h2+C12

(c)

C2=2h1+h2+C12

(d)

C2=2h1+h2-C12

Answer:

Option (b)

27.

The device which increases the pressure of a fluid at the expense of velocity drop is known as

(a)

turbine

(b)

nozzle

(c)

diffuser

(d)

boiler

Answer:

Option (c)

28.

The SFEE for diffuser is 

(a)

C1=2h2-h1-C22

(b)

C1=2h2+h1+C22

(c)

C1=2h2-h1+C22

(d)

C1=2h1-h2+C22

Answer:

Option (c)

29.

The SFEE for reciprocating compressor is

(a)

W=mh1-h2-Q

(b)

W=mh1+h2-Q

(c)

W=mh1+h2+Q

(d)

W=mh2-h1-Q

Answer:

Option (a)

30.

The SFEE for centrifugal pump is

(a)

mp1v1+C122+z1g+q=mp2v2+C222+z2g+q-W

(b)

mp1v1+C122+z1g+q=mp2v2+C222+z2g+q+W

(c)

mp1v1-C122+z1g+q=mp2v2-C222+z2g+q-W

(d)

mp1v1-C122+z1g+q=mp2v2-C222+z2g+q+W

Answer:

Option (a)

Showing 21 to 30 out of 38 Questions