NEW
Font size
WorksheetsNUMS T5 Thermodynamics
Total questions: 50
Worksheet time: 51mins
Maximum work is done in which process
Isotherm
Isobaric
Isochoric
Adiabatic
If two objects are in thermal equilibrium with each other
They cannot be moving
They cannot be at different temperatures
They cannot be undergoing an elastic collision
They cannot have different pressures
The first law of thermodynamics is concerned with conservation of
Molecules
Moles
Energy
Temperature
If a cup of tea is at 500C is allowed to cool to room temperature, heat released would be (assume room temperature to be equal to 25 o C and heat capacity of cup and tea to be 5.0 Kj/K)
25 kJ
125 kJ
200 kJ
250 kJ
If 20J of work is done in compressing a gas adiabatically the change in internal energy is equal to
20J
10J
–20J
200J
During adiabatic compression of a gas its temperature
Remains constant
Falls
Become zero
Rise
A system does 600J of work at the same time has its internal energy increased by 320J. How much heat has been supplied?
280 J
600 J
920 J
20 J
In a certain process, 400J of heat energy is supplied to a system and at the same time 150 J of work is done by the system. What is the increase in internal energy of the system?
250 J
100 J
50 J
150 J
The direction of flow of heat between two bodies is determined by
Internal energy
Total energy
Kinetic energy
None of these
Heat is.
Energy transferred by macroscopic work
Energy transferred by virtue of a temperature difference
Energy content of an object
A temperature difference
Two different samples have the same mass and temperature. Equal quantities of energy are absorbed as heat by each. Their final temperatures may be different because the samples have different
Heat capacities
Volumes
Densities
Thermal conductivities
If Cv =5/2R then Co is
2/5R
2/7R
7/2R
5/2R
The equation ∆Q=∆U represents a process
Isochoric
Isothermal
Isobaric
None
Starting with the same initial conditions, an ideal gas expands from volume V1 to V2 in three different ways. The work done by the gas is W1 if the process is purely isothermal, W2 if purely isobaric and W3 if purely adiabatic. The
W2 > W1 > W3
W2 > W3 > W1
W1 > W2 > W3
W1 > W3 > W2
A system undergoes an adiabatic process in which its internal energy increases by 20 J. Which of the following statements is true?
20 J of work was done by the system
The system received 20 J of energy as heat
20 J of work was done on the system
The system lost 20 J of energy as heat
In an adiabatic process
The energy absorbed as heat equals the work done by the system on its environment
The energy absorbed as heat equals the work done by the environment on the system
The absorbed as heat equals the change in internal energy
The work done by the environment on the system equals the change in internal energy
A gas in an insulated cylinder is compressed rapidly and its internal energy increases by 25 J. Work done during this process is
25 J
50 J
–50 J
–25 J
If volume of gas is doubled without changing its temperature, the pressure of gas is
Doubled
Reduced to one fourth of original value
Not changed
Reduced to half of original value
In which process the P–V indicator diagram is straight line parallel to volume axis?
Isobaric
Adiabatic
Isothermal
Isochoric
If the heat capacity of a 10g of a substance is 300 JK-1 then the heat capacity of 100g ____________of same substance would be equal to
300 J/K
3 J/K
3000 J/K
30 J/K
The difference between the molar specific heat at constant pressure and the molar specific heat at constant volume for an ideal gas is
The Boltzmann constant k
The universal gas constant R
The Avogadro constant NA
kT
The amount of heat energy required to raise the temperature of a body of mass 1 kg through 1 k is called:
Specific heat
Molar specific heat
Heat capacity
Heat of vaporization
The first law of thermodynamics can be stated in the form ∆U = Q – W. Which of the quantities ∆U, Q and W are necessarily zero when the system is an ideal gas that undergoes a change at constant temperature?
∆W only
∆Q only
∆U only
All of ∆U, Q, W
What is the molar specific heat of a isothermal & adiabatic process respectively
0, ∞
∞ , 0
0, 0
none of these
We can express the work in terms of
P∆U
P∆A
P∆V
All are correct
A cycle tyre bursts suddenly. This represents an
Isothermal process
Isochoric process
Isobaric process
Adiabatic process
CV of a gas is 8 cal/Kmol. Find CP/CV. Assume R = 2 cal/Kmol.
1.4
1.33
1.25
1.8
An isochoric process is one which take place at
Constant internal energy
Constant volume
Constant entropy
Constant pressure
Heat leaves the system is taken as
Positive
Neither negative nor positive
Negative
Zero
If 315cal of heat is given to the system, and the system does 20cal of work, find the change in internal energy.
335cal
295cal
335J
295 J
Internal energy of a system is defined as
The sum of kinetic energies of all molecules of the system
The sum of kinetic and potential energies of all molecules of the system
The sum of potential energies of the system
The average kinetic energy of all molecules
Suppose volume of gas in a cylinder is 3 cm3, if the piston is kept fixed and gas is heated from 5 o C to 12 o C then the work done is
2.3 J
21 J
Zero
25 J
In a science lab a student heats up a chemical from10°C to 25° C which requires thermal energy of 30000J.If the mass of object is 40 k, the specific heat capacity of the chemical would be
25 J/kgC
50 J/kgC
75 J/kgC
100 J/kgC
In an adiabatic process
W = -ΔU
–W = ΔU
∆Q=0
All of these
The heat capacity of sodium metal is 1500 J/K, if the mass of the sodium metal is 75 kg, the specific heat capacity would be
20 J/kgC
40 J/kgC
10 J/kg C
80 J/kgC
Which one is not adiabatic process
Escape of air from burst tyre
Cloud formation
Slow expansion
None
The internal energy comprises of two types of energies, those are
Mechanical and electrical energy
Kinetic and potential energy
Magnetic and electrical energy
Kinetic and magnetic energy
Heat energy added to a system under isothermal conditions appears as
Work done by the system
Work done on the system
Increase in internal energy
Increase in temperature
The area under a curve on P–V diagram represents
The state of a system
The work done on or by the system
The work done in a cyclic process
Internal energy of the system
A gas is compressed at a constant pressure of 50N/m2from a volume of 10m3 to a volume of 4m3. Energy of 100 J then added to the gas by heating. Its internal energy is
Increased by 400 J
Increased by 200 J
Increased by 100 J
Decreased by 200 J
Work done by air when it expands from 50 litres to 150 litres at a constant pressure of 2 atmospheres is
2×104 joules
2×100 joules
2×105×100 joules
2×10-5×100 joules
A milkman boils the milk before distributing it in the pots. He raises the temperature of the milk from 10 °C to 130 °C with the thermal energy of 120000 J. If the mass of the milk is 25 kg, the specific heat capacity of the milk would be
25 J/kgC
250 J/kgC
40 J/kgC
120 J/kgC
A system does 600 J of work and at the same time has its internal energy increased by 320 J. How much heat has been supplied:
280 J
600 J
920 J
200 J
According to the first law of thermodynamics, applied to a gas, the increase in the internal energy during any process:
equals the heat input minus the work done on the gas
equals the heat input plus the work done on the gas
equals the work done on the gas minus the heat input
is independent of the heat input
A system undergoes an adiabatic process in which its internal energy increases by 20 J. Which of the following statements is true?
20 J of work was done on the system
the system lost 20 J of energy as heat
20 J of work was done by the system
the system received 20 J of energy as heat
Two different samples have the same mass and temperature. Equal quantities of energy are absorbed . as heat by each. Their final temperatures may be different because the samples have different:
heat capacities
thermal conductivities
volumes
coefficients of expansion
The internal energy of an ideal gas depends on:
the temperature only
the volume only
the pressure only
the temperature and pressure only
A gas performs the most work when it expands:
Isothermally
Adiabatically
lso-barically
At non-uniform rate
Expression for isothermal process is:
Q = ΔU
ΔU = W
Q = W
ΔU = -W
Heat energy added to a system under isothermal condition appears as:
Work done by the system
Work done on the system
Increase in internal energy
Increase in temperature
