TITLE.PM5

908 ENGINEERING THERMODYNAMICS

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\M-therm\Comp1.pm5

14. A standard vapour is compressed to half its volume without changing is temperature. The
    result is that :
    (a) All the vapour condenses to liquid
    (b) Some of the liquid evaporates and the pressure does not change
    (c) The pressure is double its initial value
    (d) Some of the vapour condenses and the pressure does not change.


15. A system of 100 kg mass undergoes a process in which its specific entropy increases from
    0.3 kJ/kg-K to 0.4 kJ/kg-K. At the same time, the entropy of the surroundings decreases
    from 80 kJ/K to 75 kJ/K. The process is
    (a) Reversible and isothermal (b) Irreversible
    (c) Reversible (d) Impossible.


16. The thermodynamic parameters are :
    I. Temperature II.Specific volume
    III.Pressure IV.Enthaply
    V. Entropy
    The Clapeyron equation of state provides relationship between
    (a) I and II (b) II, III and V
    (c) III, IV and V (d) I, II, III and IV.


17. The work done in compressing a gas isothermally is given by :

(a)

γ

γ

γ

γ

−

F

HG

I

KJ

−

L

N

M

M

M

O

Q

P

P

P

−

1

11 2 1

1

1

.pV

p

p (b) mRT^1 loge^

p

p

2

1

N.m

(c) mcp (T 2 – T 1 ) kJ (d) mRT 1 1kJ^2

1

−

F

HG

I

KJ

T

T

.

18. An ideal air standard cycle is shown in the given tempera-
    ture entropy diagram (Fig. 8).

The same cycle, when represented on the pressure-volume

co-ordinates, takes the form.

p

V

2 3

1

p

V

2 3

1

(a) (b)

T

S

1

3

2

Fig. 8