The internal energy change in a system that has absorbed 2 kcal of heat and done 500 J of work is
1. 8900 J
2. 6400 J
3. 5400 J
4. 7900 J
If Q, E and W denote respectively the heat added, change in internal energy and the work done in a closed cyclic process, then
1. W=0
2. Q=W=0
3. E=0
4. Q=0
In a thermodynamic process, pressure of a fixed mass of a gas is changed in such a manner that the gas molecules absorb 30 J of heat and 10 J of work is done by the gas. If the initial internal energy of the gas was 40 J, then the final internal energy will be -
(1) 30 J
(2) 20 J
(3) 60 J
(4) 40 J
If the ratio of specific heat of a gas at constant pressure to that at constant volume is γ, the change in internal energy of a mass of gas, when the volume changes from V to 2V constant pressure p, is
(1)
(2) pV
(3)
(4)
If heat given to a system is 6 kcal and work done by the system is 6 kJ. Then the change in internal energy is :
(1) 19.1 kJ
(2) 12.5 kJ
(3) 25 kJ
(4) Zero
A vessel containing 5 litres of a gas at 0.8 m pressure is connected to an evacuated vessel of volume 3 litres. The resultant pressure inside will be (assuming whole system to be isolated)
(1) 4/3 m
(2) 0.5 m
(3) 2.0 m
(4) 3/4 m
The latent heat of vaporisation of water is 2240 J/gm. If the work done in the process of expansion of 1 g is 168 J, then increase in internal energy is
(1) 2408 J
(2) 2240 J
(3) 2072 J
(4) 1904 J
During the adiabatic expansion of 2 moles of a gas, the internal energy of the gas is found to decrease by 2 joules, the work done during the process by the gas will be equal to -
(1) 1 J
(2) –1 J
(3) 2 J
(4) – 2 J
If denotes the ratio of two specific heats of a gas, the ratio of slopes of adiabatic and isothermal PV curves at their point of intersection is
(1)
(2)
(3)
(4)
The adiabatic Bulk modulus of a perfect gas at pressure P is given by
(1) P
(2) 2P
(3) P/2
(4) γ P