| 1 |
If a molecule with momentum mv strikes a wall and rebound then the change in momentum will be:
|
A. -2 mv
B. Zero
C. 2 mv
D. mv
|
| 2 |
An isochoric process is one which take place at
|
A. Constant internal energy
B. Constant entropy
C. Constant volume
D. Constant pressure
|
| 3 |
The volume of given mass of a gas will be doubled at atmosphere pressure if the temperature of the gas is changed from 150°C to
|
A. 300°C
B. 573°C
C. 600°C
D. 743°C
|
| 4 |
The highest efficiency of a heat engine whose low temperature is 17°C and the high temperature is 200°C is
|
A. 70%
B. 100%
C. 35%
D. 38%
|
| 5 |
Generally a temperature scale is established by using certain physical properties of a material which varies
|
A. nonlinearly with temperature
B. linearly with temperature
C. either of them
D. none of them
|
| 6 |
In the study of thermodynamics, which gas is considered as the working substance
|
A. real gas
B. ideal gas
C. any gas may be ideal or real
D. none of them
|
| 7 |
When heat is added into the system then change in entropy is
|
A. negative
B. positive
C. zero
D. any one of them
|
| 8 |
A gas which strictly obeys the gas laws under all conditions of temperature and pressure is called:
|
A. Ideal gas
B. Inert gas
C. Real gas
D. None of these
|
| 9 |
A real gas can be approximated to an ideal gas at
|
A. Low density
B. High pressure
C. High density
D. Low temperature
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| 10 |
According to the second law, which is must to produce work
|
A. a source contains a large amount of heat energy
B. two sources at the same temperature
C. two sources at the different temperatures
D. a source contains a small amount of energy
|
| 11 |
Which quantity is important in stating the entropy of the system
|
A. initial entropy
B. final entropy
C. change in entropy
D. none of them
|
| 12 |
The work done on the system by the environment is considered as
|
A. positive
B. negative
C. zero
D. any one of them
|
| 13 |
Rice takes longest to cook
|
A. In a submarine 100 m below the surface of the sea
B. At sea level
C. At Murree
D. At Mount Everest
|
| 14 |
At O° K which of the following properties of a gas will be zero?
|
A. Kinetic energy
B. Potential energy
C. Vibrational energy
D. Density
|
| 15 |
A succession of events which bring the system back to its initial condition is called
|
A. reversible process
B. irreversible process
C. a cycle
D. none of them
|
| 16 |
The basis to define a temperature scale that is independent of material properties is provided by
|
A. carbon cycle
B. nitrogen cycle
C. Carnot cycle
D. irreversible cycle
|
| 17 |
Real gases strictly obey gas law at:
|
A. High pressure and low temperatures
B. Low pressures and high temperatures
C. High pressures and high temperatures
D. None of these
|
| 18 |
The internal energy of a system does not depend upon the
|
A. initial state of the system
B. final state of the system
C. path
D. none of them
|
| 19 |
In an adiabatic expansion, the temperature of the gas
|
A. increases
B. becomes zero
C. decreases
D. decreases rapidly
|
| 20 |
The state in which ice, water and vapour coexists in equilibrium is called
|
A. zero degree celsius
B. zero degree fahrenheit
C. absolute zero
D. 373 K
|
| 21 |
R.M.S velocity of a particle is V at pressure P. If pressure increases by two times, then R.M.S velocity becomes
|
A. 2V
B. 3V
C. 0.5V
D. V
|
| 22 |
The absolute temperature for an ideal gas is
|
A. directly proportional to the rotational K.E of gas molecules
B. directly proportional to the vibrational K.E of gas molecules
C. directly proportional to the average translational K.E.of gas molecules
D. directly proportional to the P.E. of gas molecules
|
| 23 |
Pressure exerted by a gas is
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A. Independent of density of the gas
B. Inversely proportional to the density of the gas
C. Directly proportional to the square of the density of the gas
D. Directly proportional to the density of the gas
|
| 24 |
On a cold morning a metal surface will fell colder to touch than a wooden surface, because
|
A. Metal has high specific heat
B. Metal has high thermal conductivity
C. Metal has low specific heat
D. Metal has low thermal conductivity
|
| 25 |
The rate of change of momentum of a molecule is equal to:
|
A. Pressure
B. Work
C. Density
D. Force
|
| 26 |
In an adiabatic process the work is done at the expense of the
|
A. energy supplied to the system
B. energy gained from the surroundings
C. internal energy
D. none of them
|
| 27 |
A reversible cycle is the one in which
|
A. some of the changes are reversible
B. all of the changes are reversible
C. all of the changes are irreversible
D. none of them
|
| 28 |
It is impossible to devise a processes which may convert heat, extracted from a single reservoir, entirely into work without leaving any change in the working system. This is the statement of
|
A. Clausius statement of second law
B. Kelvin'sstatement of second law
C. Clausius statement of first law
D. Kelvin's statement of first law
|
| 29 |
The ideal gas law is
|
A. P = nRT
B. V = nRT
C. PV =RT
D. PV =nRT
|
| 30 |
When two objects come to common temperature, the body is said to be in:
|
A. Static equilibrium
B. Dynamic equilibrium
C. Thermal equilibrium
D. None of these
|