A small sphere of radius 'r' falls from rest in a viscous liquid. As a result, heat is produced due to viscous force. The rate of production of heat when the sphere attains its terminal velocity, is proportional to
r3
r2
r4
r5
D.
r5
Power = rate of production of heat= F.V
Two moles of helium gas are taken over the cycle ABCDA, as shown in the P–T diagram. 
Assuming the gas to be ideal the work done on the gas in taking it from A to B is
When a system is taken from state i to state f along the path iaf, it is found that Q = 50 cal and W = 20 cal. Along the path’ ibf Q = 36 cal. W along the path ibf is
The work of 146 kJ is performed in order to compress one kilo mole of gas adiabatically and in this process the temperature of the gas increases by 7° C. The gas is
(R = 8.3 J mol−1 K−1 )
Which of the following is incorrect regarding the first law of thermodynamics?
A system goes from A to B via two processes I and II as shown in the figure. If ∆U1 and ∆U2 are the changes in internal energies in the processes I and II respectively, the
Which of the following statements is correct for any thermodynamic system?
Mock Test Series
