- 1)
- The change in the internal energy of a given system is equal
to the sum of the heat given to it and the work done by it (i.e.
).
- 2)
- In a constant-pressure (isobaric) process of a given system, the work
done by the system is zero.
- 3)
- In an isothermal (constant-temperature) process of an ideal
gas,
is satisfied. (
)
- 4)
- The heat capacity of a given system is independent of the
system size.
(a) Only one (b) Only two (c) Only three (d) All four (e) None
- 2
- In Fig. 1 is shown a - (pressure-volume)
diagram of a certain
gas undergoing a cyclic process. In one cycle of the cyclic process,
how much work is done by the gas? One unit of pressure and volume is
respectively and in the graph.
Figure 1:
Prob 2
|
(a) (b) (c) (d)
(e)
- 3
- A gas consists of hydrogen atoms (H) and hydrogen molecules
(). At certain thermal equilibrium of the gas, the
root-mean-square speed of a hydrogen atom is 400 m/s; what would be
the root-mean-square speed of a hydrogen molecule in this gas?
(a) 283 m/s (b) 100 m/s (c) 200 m/s (d) 800 m/s (e) None of the above
- 4
- How long does it take a 350 W coffeepot to boil off
of water initially at
.
(The density of water is
,
the latent heat of
vapourisation of water =
and the specific heat
of water is
).
(a) 6.1 min (b) 70 min (c)
(d) 31 min (e) None of
the above
- 5
- How many of the following statements are true?
- 1)
- The efficiency of a heat engine is only dependent on the
highest temperature and the lowest temperature of a cycle.
- 2)
- A refrigerator can extract heat from the lower-temperature
system and convert it completely into mechanical work.
- 3)
- A Carnot engine is an ideal engine with the perfect
(100 %) efficiency.
- 4)
- The entropy change in a reversible process is zero.
(a) Only one (b) Only two (c) Only three (d) All four (e) None