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
A Carnot engine works between temperature 72°C and 27°C. The efficiency of the engine is
70 %
30 %
0 %
10 %
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
For adiabatic process
pV = constant
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 %
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
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
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?
Boyle's law is applicable for an
adiabatic process
isothermal process
isobaric process
isochoric process
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