SSC JE 11 Oct 2023 PAPER I Mechanical Part 5

Q.1 A Carnot cycle operates between two temperatures T1 and T2. The efficiency of the cycle is given by η = (T1 − T2) / T1. Which of the following statements is correct?

1. The efficiency of the Carnot cycle is always equal to that of any other heat engine operating between the same two temperatures.
2. The efficiency of the Carnot cycle depends on the working substance used.
3. The efficiency of the Carnot cycle is always less than that of any other heat engine operating between the same two temperatures.
4. The efficiency of the Carnot cycle is always greater than that of any other heat engine operating between the same two temperatures.

Correct Option: 4

Q.2 If a turbine is working under different heads, the behaviour of the turbine can be easily determined from the values of _______________.

1. blade angles
2. number of vanes
3. unit quantities
4. size of runner

Correct Option: 3

Q.3 A seamless pipe having a diameter of 600 mm and thickness of 9 mm, contain the fluid under a pressure of 4 MPa, find the longitudinal stress developed in the pipe.

1. 133.3 Mpa
2. 66.6 Mpa
3. 88.8 Mpa
4. 77.7 Mpa

Correct Option: 2

SSC JE 11 Oct 2023 PAPER I Mechanical Part 5

Q.4 The speed ratio for an impulse turbine can be taken as __________.

1. 0.45
2. 0.6
3. 0.3
4. 0.75

Correct Option: 1

Q.5 The Molten metal is used in ___________ process

1. Machining
2. Casting
3. Deep Drawing
4. Forging

Correct Option: 2

Q.7 Which of the following milling operations is used to produce a flat surface parallel to the axis of rotation of the cutter?

1. Profile milling
2. End milling
3. Face milling
4. Plain milling

Correct Option: 4

SSC JE 11 Oct 2023 PAPER I Mechanical Part 5

Q.8 The duplex feed pump is:

1. Axial-flow pump
2. Single-acting reciprocating pump
3. Centrifugal pump
4. Double-acting reciprocating pump

Correct Option: 4

Q.9 The behaviour of a material at different stages of loading is represented by a diagram called the _________ diagram.

1. hysteresis
2. circumferential stress
3. stress strain
4. iron carbon

Correct Option: 3

Q.10 The mass of water evaporated per unit mass of fuel burnt is termed as _________ steam boilers.

1. boiler performance of
2. actual evaporation in
3. equivalent evaporation in
4. boiler efficiency of

Correct Option: 2

Q.11 Which of the following is a water-tube boiler?

1. Cochran boiler
2. Lancashire boiler
3. Cornish boiler
4. Babcock & Wilcox boiler

Correct Option: 4

SSC JE 11 Oct 2023 PAPER I Mechanical Part 5

Q.12 In air-conditioning of aeroplanes, using air as a refrigerant, the cycle used is:

1. reversed Carnot cycle
2. reversed Otto cycle
3. reversed Joule cycle
4. reversed Brayton cycle

Correct Option: 4

Q.13 Which impellers are more likely to be clogged if stringy material or solids are pumped?

1. Cannot be predicted
2. Semi-open impeller
3. Closed impeller
4. Open impeller

Correct Option: 3

Q.14 The highest temperature during the cycle, in a vapour compression refrigeration system, occurs after:

1. condensation
2. compression
3. evaporation
4. expansion

Correct Option: 2

Q.15 Which of the following is the correct relation for specific speed of turbine?

1. Specific speed is directly proportional to shaft power
2. Specific speed is directly proportional to head under which the turbine is working
3. Specific speed is directly proportional to square of the head under which the turbine is working
4. Specific speed is directly proportional to square root of shaft power

Correct Option: 4

SSC JE 11 Oct 2023 PAPER I Mechanical Part 5

Q.17 In a mechanical draught system, draught is produced by a _____________.

1. pump
2. chimney
3. chain grate stoker
4. blower

Correct Option: 4

Q.18 For the same compression ratio, which of the following processes will require the least compression work?

1. Adiabatic process
2. Isochoric process
3. Polytropic process
4. Isothermal process

Correct Option: 4

SSC JE 11 Oct 2023 PAPER I Mechanical Part 5

Q.19 There are two horizontal pipes in which water is flowing. If we have to find the pressure difference between these two horizontal pipes using an inverted manometer, and two manometric fluids with specific gravities of 13.5 and 0.9 are available, then which manometric fluid will be appropriate?

1. Fluid with the specific gravity of 13.5
2. Cannot be predicted
3. Fluid with the specific gravity of 0.9
4. Both the fluids can be used

Correct Option: 3

Q.20 In the shaping process, the cutting tool moves _________.

1. in a circular motion
2. in a straight line
3. in an elliptical motion
4. in a parabolic motion

Correct Option: 2

Q.21 For a two-stage reciprocating air compressor, the section pressure is 1.6 bar and the delivery pressure is 40 bar. What is the value of the ideal intercooler pressure (in bar)?

1. 9
2. 4.56
3. 8
4. 20.8

Correct Option: 3

Q.22 The property of tool material to retain its hardness at elevated temperature is known as:

1. Toughness
2. Plasticity
3. Red hardness
4. Elasticity

Correct Option: 3

SSC JE 11 Oct 2023 PAPER I Mechanical Part 5

Q.23 Which of the following statements is true regarding vapour-compression refrigeration system (VCRS)?

1. VCRS with both water cooled and air cooled condenser will require same power for same refrigeration effect.
2. Power consumption of VCRS with air cooled condenser may be lesser or greater than that of VCRS with water cooled condenser.
3. Power consumption of VCRS with air cooled condenser is more as compared to that of VCRS with water cooled condenser.
4. Power consumption of VCRS with air cooled condenser is less as compared to that of VCRS with water cooled condenser.

Correct Option: 3

Q.24 The enthalpy of water is considered as ‘zero’ at _______.

1. 0.01°C
2. 100°C
3. 37°C
4. 4°C

Correct Option: 1

Q.25 A rectifier is fitted in an ammonia absorption plant to:

1. remove the unwanted water vapour by cooling the vapour mixture and condensing the water vapour
2. superheat ammonia vapour
3. only remove the unwanted water vapour by cooling the vapour mixture
4. remove the unwanted water vapour by heating the vapour mixture

Correct Option: 1

SSC JE 11 Oct 2023 PAPER I Mechanical Part 5