| 1 |
The earliest heat engine was
|
A. petrol engine
B. diesel engine
C. electric engine
D. steam engine
|
| 2 |
If 42 J heat is transferred to the system and the work done by the system is 32 J then what will be the change in internal energy
|
A. 0 J
B. 2 J
C. 5 J
D. 10 J
|
| 3 |
While deriving equation of pressure by kinetic theory of gases, we take into account:
|
A. Only linear motion of molecules
B. Only rotational motion
C. Only vibratory motion
D. All of these
|
| 4 |
Electromagnetic waves emitted by hot bodies are called:
|
A. Photoelectrons
B. Alpha rays
C. Thermal radiation
D. None of these
|
| 5 |
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
|
| 6 |
A process in which no heat enters or leaves the system is called
|
A. isochoric process
B. isothermal process
C. adiabatic process
D. none of them
|
| 7 |
The curve representing an isothermal process is called
|
A. adiabat
B. isotherm
C. fixed temperature
D. none of them
|
| 8 |
The nature of thermal radiation is similar to:
|
A. Ultraviolet rays
B. Light rays
C. Both of them
D. None of these
|
| 9 |
If the distance between two charges is doubled, the force between them will become:
|
A. Double
B. Half
C. Three times
D. One fourth
|
| 10 |
On the exaust stroke, the outlet values opens. The residual gases are expelled and piston moves
|
A. outwards
B. inwards
C. in either way
D. none of these
|
| 11 |
Heat travels through vacuum by
|
A. Conduction
B. Convection
C. Radiation
D. Both A and B
|
| 12 |
Pressure of a gas at constant volume is proportion to
|
A. Total energy of gas
B. Average P.E to molecules
C. Average K.E of molecules
D. Total internal energy of gas
|
| 13 |
Since the absolute scale is independent of the property of the working substance, hence, can be applied at
|
A. very high temperature
B. very low temperature
C. any one of them
D. none of them
|
| 14 |
In all natural processes where heat flows from one system to another, there is always a net
|
A. decrease in entropy
B. increase in entropy
C. decrease or increase in entropy
D. none of them
|
| 15 |
At what temperature the adiabatic change is equivalent to the isothermal change?
|
A. Zero degree Celsius
B. Zero Kelvin
C. Critical temperature
D. Above critical temperature
|
| 16 |
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
|
| 17 |
If N is the total number of molecules and V is the volume of the container, then the expression for the pressure of gas is
|
A. P=P/V<1/2mv2>
B. P=2N/V<1/2mv2>
C. P=2/3N/V<1/2mv2>
D. P=2/3N/V<mv2>
|
| 18 |
The percentage of available heat energy converted into work by a petrol engine is roughly
|
A. 35 %
B. 40 %
C. 35 to 40 %
D. 25 %
|
| 19 |
Pressure applied at any point of gas at rest is transmitted equally to all parts of the gas. This is the statement of:
|
A. Newton's second law
B. Pascal's law
C. Carnot theorem
D. Second law of thermodynamics
|
| 20 |
No spark plug is needed in
|
A. petrol engine
B. diesel engine
C. both of them
D. none of them
|
| 21 |
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
|
| 22 |
The efficiency of carnot engine cannot be 100% or one unless cold reservoir is at
|
A. 100 K
B. 273 K
C. 0 K
D. -273 K
|
| 23 |
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
|
| 24 |
The internal energy of an ideal gas system is generally the
|
A. translational K.E of molecules
B. vibrational K.E of molecules
C. rotational K.E of molecules
D. all of them
|
| 25 |
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
|
| 26 |
The disorder in the system increases due to the
|
A. removal of heat
B. addition of heat
C. removal or addition of heat
D. none of them
|
| 27 |
The kinetic energy of one molecule of a gas at normal temperature and pressure will be (k = 8.31 J/mole K) :
|
A. 1.7 x 103J
B. 10.2 x 103J
C. 3..4 x 103J
D. 6.8 x 103J
|
| 28 |
A process which can be retraced in exactly reverse order, without producing any change in the surroundings is called
|
A. reversible process
B. irreversible process
C. any one of them
D. none of them
|
| 29 |
Which of the following is a state variable
|
A. entropy
B. pressure
C. volume
D. all of them
|
| 30 |
At constant volume temperature is increased. Then
|
A. Collision on walls will be less
B. Number of collisions per unit time will increase
C. Collision will be in straight lines
D. Collision will not change
|