ESE ME 2019: Thermodynamics Quiz-2 for ESE & GATE ME Exams

Question 1

A heat engine working on the Carnot cycle receives heat at the rate of 50 kW from a source at 1300 K and rejects it to a sink at 400 K. The heat rejected is

Question 2

The choice of a refrigerant depends upon:
1) Refrigerating capacity
2) Type of compressor used (reciprocating, centrifugal or screw)
3) Service required (whether for air conditioning, cold storage or food freezing)
Which of the above statements is/are correct?

Question 3

The Orsat apparatus gives
1) Volumetric analysis of dry products of combustion
2) Gravimetric analysis of dry products of combustion
Which of the above statements is/are correct?

Question 4

Consider the following statements:
1) Thermal efficiency of the simple Steam or Ranking cycle can be improved by increasing the maximum system pressure and temperature
2) Increasing the superheat of the steam improves the specific work and decreases the moisture content of exhaust steam
3) Increasing maximum system pressure always increases the moisture content at the turbine exhaust
4) Lowering the minimum system pressure increases the specific work of the cycle
Which of the above statements are correct?

Question 5

Direction: Each of the question consist of two statements, one labeled as the ‘Statement (I)’ and the other as ‘Statement (II)’. Examine these two statements carefully and select the answer to these items using the codes given below:

Statement (I): Effective temperature is an index which co-relates the combined effect of air temperature, air humidity and air movement upon human thermal comfort.
Statement (II): Thermal comfort is not affected by mean radiant temperature.

Question 6

Direction: Each of the question consist of two statements, one labeled as the ‘Statement (I)’ and the other as ‘Statement (II)’. Examine these two statements carefully and select the answer to these items using the codes given below:

Statement (I): Automotive Petrol engines require Petrol of Octane number between 85-95
Statement (II): Automotive Diesel engines require Diesel oil of Cetane number between 85-95

Question 7

Consider the following statements regarding supercharging of CI engines:
1). Supercharging results in quieter and smoother operation of a CI engine
2). Supercharging of a CI engine requires increase in value overlap
3). The limit of supercharging for a CI engine is reached by thermal and mechanical loading.
Which of the above statements are correct?

Question 8

Direction: Each of the next consists of two statements, one labeled as the ‘Assertion (A)’ and the other as ‘Reason (R)’. You are to examine these two statements carefully and select the answers to these items using the codes given below:

Assertion (A): In a diesel engine knocking decreases with reduced engine speed.
Reason (R): With increased engine speed, quantity of fuel injected during the delay period increases.

Question 9

Fuel injection in CI engine refers to injection of ___________.

Question 10

A refrigerator operating on standard vapour compression cycle has COP = 5.5 and is driven by 40 kW compressor. Saturated liquid and saturated vapour enthalpies at condensing temperature of 30^oC are 69.55 kJ/kg and 201.45 kJ/kg respectively. saturated refrigerant vapour leaving the evaporator has enthalpy of 187.53 kJ/kg. Find refrigerant temperature at compressor discharge. (Take CP of refrigerant vapour as 0.6155 kJ/kgK.)