Questions and answers for exam Preparation

MCQs

Laws Of Thermodynamics

Total Questions : 1462 | Page 5 of 147 pages

Question 41. The absolute pressure of a given mass of a perfect gas varies inversely as its volume, when the temperature remains constant. This statement is known as Charles' law.

Yes
No
Can't say
None of these

Discuss Question

Answer: Option B. -> No
Answer: (b).No

Question 42. The dual combustion cycle consists of one constant pressure, two constant volume and two isentropic processes.

Agree
Disagree
Can't say
None of these

Discuss Question

Answer: Option A. -> Agree
Answer: (a).Agree

Question 43. The total energy of a molecule is shared equally by the various degrees of freedom possessed by it. This law is known as

law of equipartition of energy
law of conservation of energy
law of degradation of energy
none of these

Discuss Question

Answer: Option A. -> law of equipartition of energy
Answer: (a).law of equipartition of energy

Question 44. Kelvin-Planck's law deals with

conservation of work
conservation of heat
conversion of heat into work
conversion of work into heat

Discuss Question

Answer: Option C. -> conversion of heat into work
Answer: (c).conversion of heat into work

Question 45. Otto cycle efficiency is higher than Diesel cycle efficiency for the same compression ratio and heat input because in Otto cycle

combustion is at constant volume
expansion and compression are isentropic
maximum temperature is higher
heat rejection is lower

Discuss Question

Answer: Option D. -> heat rejection is lower
Answer: (d).heat rejection is lower

Question 46. The free expansion process is __________ non-flow process.

reversible
irreversible
Can't say
None of these

Discuss Question

Answer: Option B. -> irreversible
Answer: (b).irreversible

Question 47. Liquid fuels have higher calorific value than solid fuels.

Yes
No
Can't say
None of these

Discuss Question

Answer: Option A. -> Yes
Answer: (a).Yes

Question 48. A mixture of gas expands from 0.03 m³ to 0.06 m³ at a constant pressure of 1 MPa and absorbs 84 kJ of heat during the process. The change in internal energy of the mixture is

30 kJ
54 kJ
84 kJ
114 kJ

Discuss Question

Answer: Option B. -> 54 kJ
Answer: (b).54 kJ

Question 49. The gas constant (R) is equal to the __________ of two specific heats.

sum
difference
product
ratio

Discuss Question

Answer: Option B. -> difference
Answer: (b).difference

Question 50. According to Avogadro's law

the product of the gas constant and the molecular mass of an ideal gas is constant
the sum of partial pressure of the mixture of two gases is sum of the two
equal volumes of all gases, at the same temperature and pressure, contain equal number of molecules
all of the above

Discuss Question

Answer: Option C. -> equal volumes of all gases, at the same temperature and pressure, contain equal number of molecules
Answer: (c).equal volumes of all gases, at the same temperature and pressure, contain equal number of molecules