Test: Thermodynamics- 2

QUESTION: 1

At critical point enthalpy of vaporizations is

A.
maximum
B.
zero
C.
minimum
D.
changes with pressure and temperature.

Solution:

QUESTION: 2

A carnot engine is made to work on amonoatomic gas first (g = 1.67) and then on adia atomic gas (g = 1.4). Among the two whichwill have better efficiency

A.
Monoatomic
B.
Both has equal efficiency
C.
Diatomic
D.
Cannot be predicted

Solution:

QUESTION: 3

Two carnot engine are in series operatingbetween source temperature of 180º C and 20ºCsink temperature. If both produce equal amountof work the intermediated temperature is.

A.
80 ºC
B.
100 ºC
C.
50 ºC
D.
150 ºC

Solution:

QUESTION: 4

Which law of thermodynamics predicts the degree of completion of chemical reactions.

A.
Zeroth law
B.
2^nd law
C.
First law
D.
3^rd law

Solution:

QUESTION: 5

Entropy of the universe

A.
Is constant
B.
Decreases continuously
C.
Is conserved
D.
Increases continuously

Solution:

QUESTION: 6

Isentropic flow is always
1. zero increase in entropy flow.
2. revertrible adiabatic flow.
3. Frictionless reversible flow.

A.
1 and 2
B.
2 and 3
C.
1 only
D.
1,2 and 3

Solution:

In fluid dynamics, an isentropic flow is a fluid flow that is both adiabatic and reversible. That is, no heat is added to the flow, and no energy transformations occur due to friction or dissipative effects. For an isentropic flow, entropy density can vary between different streamlines.

QUESTION: 7

If the entropy of a system increases it means.

A.
Availability Increases
B.
Pressure decrease
C.
Temperature increases
D.
Degradation of energy

Solution:

QUESTION: 8

The energy of an isolated system is

A.
Is zero
B.
Decreases
C.
Increases
D.
Constant

Solution:

QUESTION: 9

Joule thomson coefficient is the slope of constantenthalpy lines in

A.
T-s diagram
B.
P-T diagram
C.
P-v diagram
D.
P-s diagram

Solution:

QUESTION: 10

With increase of pressure latent heat of steam

A.
Remains same
B.
Decreases
C.
Increases
D.
unpredictable

Solution:

QUESTION: 11

For a pure substance, the degree of freedom forsaturated vapour and superheated vapour are

A.
1 and 2
B.
1 and 1
C.
2 and 1
D.
2 and 2

Solution:

QUESTION: 12

At tripple point of water which of the followingcan be found.

A.
Ice
B.
Steam
C.
Water
D.
All of the above

Solution:

QUESTION: 13

The term which can differentiate thermodynamics from other sciences is ____.

A.
Pressure
B.
Temperature
C.
Mass
D.
none of the above

Solution:

QUESTION: 14

When water is heated from 0º C its specificvolume will,

A.
Remain constant
B.
Decrease
C.
Increase
D.
First decrease then increase

Solution:

QUESTION: 15

Which of the following is a pure substance
i. Gaseous combustion product
ii. Dry air
iii. Moist Air

A.
i
B.
i, ii
C.
i, ii, iii
D.
none

Solution:

QUESTION: 16

During boiling vapour pressure is _______ toatmospheric pressure.

A.
equal
B.
greater
C.
smaller
D.
unpredictible

Solution:

QUESTION: 17

Change of state ex. freezing, melting, evaporationetc. are

A.
Isobaric process
B.
Isochoric process
C.
Isothermal process
D.
Adiabatic process

Solution:

QUESTION: 18

First law of thermodynamics provides

A.
a statement that energy balance occurs when a system undergoes the change of state or the process
B.
a statement about whether the change of state or the process is at all feasible or not
C.
both a. and b.
D.
none of the above