CBSE
An ideal gas heat engine operates in Carnot cycle between 227°C and 127C. It absorbs 6 x 104 cal of heat at higher temperature. Amount of heat converted into work is
1.2 x 104 cal
2.2 x 104 cal
6.0 x 104 cal
4.8 x 104 cal
If 300 ml of a gas at 27° C is cooled to 7° C at constant pressure, then its final volume will be
540 mL
350 mL
280 mL
135 mL
For adiabatic process
pV = constant
An ice at -50°C is to be converted into vapour at 100°C. The heat required in this process is
1028 calorie
624 calorie
745 calorie
810 calorie
The neutral temperature of a thermocouple is 300°C. What is the inversion temperature, if the temperature of cold junction is l0°C?
590°C
610°C
310°C
290°C
In an adiabatic process, the state of a gas is changed from P1, V1, T1 to P2, V2, T2. Which of the following relation is correct?
During adiabatic expansion, the volume of air increases by 4%. The percentage decrease in the pressure will be
3.2 %
5.6 %
1.5 %
4.8 %
Boyle's law is applicable for an
adiabatic process
isothermal process
isobaric process
isochoric process
A Carnot engine works between temperature 72°C and 27°C. The efficiency of the engine is
70 %
30 %
0 %
10 %
A gas at state A changes to state B through path I and II as shown in figure. The change in internal energy is ΔU1 and ΔU2 respectively. Then :
ΔU1 > ΔU2
ΔU1 < ΔU2
ΔU1 = ΔU2
ΔU1 = ΔU2 = 0