GATE ME 2014 Set 3 | Entropy and Irreversibility Question 7 | Thermodynamics

GATE ME 2014 Set 3

MCQ (Single Correct Answer)

-0.3

Which one of the following pairs of equations describes an irreversible heat engine?

$$\oint {\delta Q} > 0\,\,$$ and $$\oint {{{\delta Q} \over T}} < 0$$

$$\oint {\delta Q} > 0\,\,\,\,and\,\,\,\oint {{{\delta Q} \over T}} < 0$$

$$\oint {\delta Q} > 0\,\,\,\,and\,\,\,\oint {{{\delta Q} \over T}} > 0$$

$$\oint {\delta Q} < 0\,\,\,\,and\,\,\,\oint {{{\delta Q} \over T}} > 0$$

GATE ME 2010

MCQ (Single Correct Answer)

-0.3

One kilogram of water at room temperature is brought into contact with a high temperature thermal reservoir. The entropy change of the universe is

equal to entropy change of the reservoir

equal to entropy change of water

equal to zero

always positive

GATE ME 2009

MCQ (Single Correct Answer)

-0.3

If a closed system is undergoing an irreversible process, the entropy of the system

Must increase

Always remains constant

Must decrease

Can increase, decrease or remain constant

GATE ME 2008

MCQ (Single Correct Answer)

-0.3

$$2$$ moles of oxygen are mixed adiabatically with another $$2$$ moles of oxygen in mixing chamber, so that the final total pressure and temperature of the mixture become same as those of the individual constituents at, their initial states. The universal gas constant is given as $$R$$. The change in entropy due to mixing, per mole of oxygen, is given by

$$-R$$ $$ln2$$

$$0$$

$$R$$ $$ln2$$

$$R$$ $$ln4$$