CBSE
Multiple Choice QuestionsA body of specific heat 0.2 kcal/ kg° C is heated through 100°C. The percentage increase in its mass is
9%
9.3×10-11 %
10%
None of these
A monoatomic gas supplied the heat Q very slowly keeping the pressure constant. The work done by the gas will be
We consider a thermodynamic system. If ΔU represents the increase in its internal energy and W the work done by the system, which of the following statements is true?
ΔU = -W in an adiabatic process
ΔU = W in an isothermal process
ΔU = -W in an isothermal process
ΔU = W in an adiabtic process
The work of 146 kJ is performed in order to compress one kilo mole of a gas adiabatically and in this process the temperature of the gas increases by 7°C. The gas is (R= 8.3J mol-1 K-1 )
diatomic
triatomic
a mixture of monoatomic and diatomic
monoatomic
Which of the following parameters does not characterise the thermodynamic state of matter?
Temperature
Pressure
Work
Volume
Which of the following processes is reversible?
Transfer of heat by radiation
Electrical heating of a nichrome wire
Transfer of heat by conduction
Isothermal compression
In isothermal process, which of the following is not true?
Temperature remains constant
Internal energy does not change
No heat enters or leaves the system
none of the above
An ideal gas heat engine operates in Carnot cycle between 227o C and 127o C. It absorbs 6 × 104 cal of heat at higher temperature. Amount of heat converted to work is
2.4 × 104 cal
6 × 104 cal
1.2 × 104
4.8 × 104 cal
A perfect gas is found to obey the relation PV3/2 = constant during an adiabatic process. If such a gas initially at a temperature T, is compressed to half of its initial volume, then its final temperature will be :
2 T
4T
(2)1/2 T
2 (2)1/2 T
A raft of wood of mass 120 kg floats in water. The weight that can be put on the raft to make it just sink, should be (d raft = 600 kg/m3)
80 kg
50 kg
60 kg
30 kg
