# One hundredth of a kilogram of air is compressed in a piston-cylinder device. At an instant of time when T=400 K, the rate at which work is being done on the air is 8.165 kW, and heat is being done on the air is 8.165 kW, and heat is being removed at a rate of 1.0 Kw, the rate of temperature rise will be

1.  10 K/s

2.  100 K/s

3.  1000 K/s

4.  10000 K/s

4

1000 K/s

Explanation :
No Explanation available for this question

# For which of the following situations, zeroth law of thermodynamics will not be valid

1.  50 cc of water at 250C mixed with 150 cc of water at 250C

2.  500 cc of milk at 150C are mixed with 100 cc of water at 150C

3.  5 kg of west steam at 1000C is mixed with 50 kg of dry and saturated steam at 1000C

4.  10 cc of water at 200C are mixed with 10 cc of sulphuric acid at 200C.

4

10 cc of water at 200C are mixed with 10 cc of sulphuric acid at 200C.

Explanation :
No Explanation available for this question

# Figure shows a vessel divided into parts by a diaphragm. The space A contains a gas and space B is evacuated. Now if the diaphragm is punctured, the gas will expand into the evacuated space B. Which of the following statement is invalid

1.  A free expansion is a non-quasistatic process

2.  The pressure and volume of gas are not related through the equation of states

3.  The process is irreversible

4.  The energy is transferred to the system

4

The energy is transferred to the system

Explanation :
No Explanation available for this question

# In which case the work done is negative

1.  A rigid steel vessel containing steam at a temperature of 1100C is left standing in the atmosphere which is at a temperature of 320C

2.  One kg of air flows adiabatically from the atmosphere into a previously evacuated bottle

3.  A rigid vessel containing ammonia gas is connected through a valve to an evacuated rigid vessel. The vessels, the valve and the connecting pipe are well insulated. The valve is opened and after a time, conditions through the two vessels become uniform

4.  A mixture of ice and water is contained in an insulated vertical cylinder closed at the top by a non-conducting piston; the upper surface is exposed to the atmosphere. The piston is held stationary while the mixture is stirred by means of a paddle-wheel protruding through the cylinder wall as a result some of the ice melts

5.  Both (b) and (d)

5

Both (b) and (d)

Explanation :
No Explanation available for this question

# Figure below shows thermodynamic expansion processes A, B, C and D. which line is closest to the isentropic process

1.  A

2.  B

3.  C

4.  D

4

C

Explanation :
No Explanation available for this question

# A pressure-volume diagram for some engine is shown in figure A. This diagram has been closely translated into temperature-entropy diagram in figure B. The point x shown on p-V diagram is represented on T-s diagram by

1.  Point S

2.  Point P

3.  Point Q

4.  Point R

4

Point S

Explanation :
No Explanation available for this question

# The relation pVγ =constant, where γ is the ratio of the specific heats of ideal gas, is applicable to

4.  Only isothermal process

4

Explanation :
No Explanation available for this question

# If a closed system obeys the following form of the first law equation, dq = du + pdv

1.  It is a simple compressible system undergoing reversible process

2.  It is a pure substance undergoing infinitesimal process

3.  It is undergoing an irreversible process

4.  It is undergoing an isentropic process

4

It is a simple compressible system undergoing reversible process

Explanation :
No Explanation available for this question

# If during a process, the temperature and pressure of system are related by T2/T1 = (p2/p1)γ-1/γ. Then the system consists of

1.  Any gas undergoing an adiabatic process

2.  An ideal gas undergoing a polytrophic process

3.  Any pure substance undergoing an adiabatic process

4.  An ideal gas undergoing a reversible adiabatic process

4

An ideal gas undergoing a reversible adiabatic process

Explanation :
No Explanation available for this question

# A cast weighing 2 kg jumps from the floor to a window 1.5m high. Neglecting the air drag, work done by the cat is

1.  Zero

2.  Nearly 30 Nm

3.  3 Nm

4.  None of these

4