Mechanical System Design - Test Set - 2

1)   Which criteria of failure is used to indicate St Venent's theory?

a. Maximum principle stress theory
b. Maximum principle strain theory
c. Shear stress theory
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Maximum principle strain theory

Explanation:
No explanation is available for this question!


2)   The ratio of di / t for thick cylinder is __________
(where di = inner diameter, t = wall thickness)


a. greater than 20
b. less than 20
c. equal to 20
d. none of the above
Answer  Explanation  Related Ques

ANSWER: less than 20

Explanation:
No explanation is available for this question!


3)   A cylinder made of plain carbon steel has inner diameter 100 mm. What is the thickness of cylinder if maximum internal pressure of 20 Mpa acts on it? ( σall = 100 N/mm2 & poisson's ratio = 0.3)

a. 11 mm
b. 15.36 mm
c. 22.32 mm
d. 80 mm
Answer  Explanation  Related Ques

ANSWER: 11 mm

Explanation:
No explanation is available for this question!


4)   What does DFMA stand for?

a. Design for Manual Assembly
b. Design for Manufacture and Assembly
c. Both a. and b.
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Both a. and b.

Explanation:
No explanation is available for this question!


5)   Which of the following principle recognizes human capabilities and limitations using design effective handling equipment?

a. Safety principle
b. Obsolescence principle
c. Ecology principle
d. Ergonomic principle
Answer  Explanation  Related Ques

ANSWER: Ergonomic principle

Explanation:
No explanation is available for this question!


6)   Which type of welded joints are not included in class 3 pressure vessels?

a. Double welded butt joint with full penetration
b. Single welded but joint with back strip
c. Single full fillet lap joints
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Single full fillet lap joints

Explanation:
No explanation is available for this question!


7)   Class 3 pressure vessels having welded joints are __________

a. fully radio-graphed
b. partially radio-graphed
c. spot radio-graphed
d. not radio-graphed
Answer  Explanation  Related Ques

ANSWER: not radio-graphed

Explanation:
No explanation is available for this question!


8)   Design pressure for unfired pressure vessels is 1.05 times of _______

a. minimum working pressure
b. maximum working pressure
c. hydrostatic test pressure
d. none of the above
Answer  Explanation  Related Ques

ANSWER: maximum working pressure

Explanation:
No explanation is available for this question!


9)   Internal pressure of 2.5 Mpa acts on a pressure vessel of thickness 15 mm and internal diameter of 1500 mm. What is the stress induced in longitudinal direction?

a. 36.63 N/mm2
b. 59.13 N/mm2
c. 65.62 N/mm2
d. 131.25 N/mm2
Answer  Explanation  Related Ques

ANSWER: 65.62 N/mm2

Explanation:
No explanation is available for this question!


10)   Which type of formed threads are used for vertical pressure vessels in the pressure range of 0.1 N/mm2 to 1.5 N/mm2?

a. Plain formed head
b. Torispherical dished head
c. Semi-elliptical dished head
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Torispherical dished head

Explanation:
No explanation is available for this question!


11)   Single cylinder four stroke engine has brake power of 8 kW and brake mean effective pressure of 0.55 Mpa. What is the length of cylinder which is 1.2 times of bore diameter? (n = 3000 rpm)

a. 110 mm
b. 103 mm
c. 70 mm
d. 65 mm
Answer  Explanation  Related Ques

ANSWER: 103 mm

Explanation:
No explanation is available for this question!


12)   Which of the following parts of piston act as bearing for connecting rod side thrust?

a. Reinforcing ribs
b. Piston barrel
c. Piston gudgeon
d. Piston skirt
Answer  Explanation  Related Ques

ANSWER: Piston skirt

Explanation:
No explanation is available for this question!


13)   What is the function of gudgeon pin?

a. Acts as stiffeners
b. Supports piston head
c. Connects piston to connecting rod
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Connects piston to connecting rod

Explanation:
No explanation is available for this question!


14)   A piston has allowable tensile stress of 50 N/mm2 and has bore diameter 150 mm. Considering strength of piston, what will be the thickness of piston head if maximum pressure of 10 N/mm2 acts on it?

a. 29 mm
b. 35 mm
c. 53 mm
d. Insufficient data
Answer  Explanation  Related Ques

ANSWER: 29 mm

Explanation:
No explanation is available for this question!


15)   A piston made of gray cast iron has piston head thickness of 20 mm. What will be thickness of piston barrel under piston rings if it has allowable tensile stress of 30 N/mm2? ( Bore diameter = 50 mm & Pmax =15 N/mm2)

a. 10 mm
b. 20 mm
c. 30 mm
d. Insufficient data
Answer  Explanation  Related Ques

ANSWER: 20 mm

Explanation:
No explanation is available for this question!


16)   Failure rate for safety valve working for 400 hours is 3 x 10–6 failures/hour. What is the reliability of safety valve?

a. 0.998
b. 0.989
c. 0.888
d. 0.899
Answer  Explanation  Related Ques

ANSWER: 0.998

Explanation:
No explanation is available for this question!


17)   If a relief valve has reliability of 0.989, how many failures are expected in testing 1000 such relief valves?

a. 111
b. 100
c. 10
d. 11
Answer  Explanation  Related Ques

ANSWER: 11

Explanation:
No explanation is available for this question!


18)   What is meant by mean time to failure (MTTF)?

a. Mean time between two successive failure components
b. Maximum time between two successive failure components
c. Sum of survival time for number of components divided by number of failures
d. Sum of number of failures divided by survival time for number of components
Answer  Explanation  Related Ques

ANSWER: Sum of survival time for number of components divided by number of failures

Explanation:
No explanation is available for this question!


19)   A plain carbon steel has mean yield strength of 300 N/mm2 and standard deviation of 50 N/mm2. What is the mean and standard deviation of margin of safety, if mean tensile stress of 250 N/mm2 and standard deviation of 65 N/mm2 acts on it?

a. 23.45 N/mm2, 50 N/mm2
b. 50 N/mm2, 82 N/mm2
c. 82 N/mm2, 7.07 N/mm2
d. 7.07 N/mm2, 50 N/mm2
Answer  Explanation  Related Ques

ANSWER: 50 N/mm2, 82 N/mm2

Explanation:
No explanation is available for this question!


20)   What causes infant mortality in mechanical equipments?

a. Design errors
b. Manufacturing defects
c. Installation defects
d. All of the above
Answer  Explanation  Related Ques

ANSWER: All of the above

Explanation:
No explanation is available for this question!


21)   Which of the following statements is true for structure/speed diagrams?

a. Structure diagrams gives range ratio of spindle speeds
b. Speed diagrams do not give range ratio of spindle speeds
c. Speed diagrams consider motor speed
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Speed diagrams consider motor speed

Explanation:
No explanation is available for this question!


22)   What is the purpose of using a gear box?

a. To increase torque
b. To increase speed
c. Converts single input speed into multiple output speeds
d. All of the above
Answer  Explanation  Related Ques

ANSWER: All of the above

Explanation:
No explanation is available for this question!


23)   Ratio of two spindle speeds is constant in _________ progression.

a. Arithmetic
b. Geometric
c. Harmonic
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Geometric

Explanation:
No explanation is available for this question!


24)   What is harmonic progression?

a. Difference between reciprocal of two successive spindle speeds is constant
b. Difference between two successive spindle speeds is constant
c. Ratio of two successive spindle speeds is constant.
d. Ratio of two successive spindle speeds is variable.
Answer  Explanation  Related Ques

ANSWER: Difference between reciprocal of two successive spindle speeds is constant

Explanation:
No explanation is available for this question!


25)   Diameter range is high in geometric progression due to _________ spindle speed.

a. low
b. high
c. constant
d. none of the above
Answer  Explanation  Related Ques

ANSWER: low

Explanation:
No explanation is available for this question!


26)   Which of the following statements is false for troughed belt conveyors?

1. Troughed belt conveyors use flexible belts
2. They contain five idlers
3. Depth of trough decreases with increasing number of idlers
4. Flexibility of belt increases as depth of trough decreases


a. 1 and 2
b. 2 and 3
c. 3 and 4
d. None of the above
Answer  Explanation  Related Ques

ANSWER: 3 and 4

Explanation:
No explanation is available for this question!


27)   Which belt conveyor prevents sliding down of material at an inclination of 55o with horizontal?

a. Flat belt conveyor
b. Troughed belt conveyor
c. Blanket belt conveyor
d. Woven wire belt conveyors
Answer  Explanation  Related Ques

ANSWER: Blanket belt conveyor

Explanation:
No explanation is available for this question!


28)   What are bulk loads?

a. Lump of material
b. Single rigid mass
c. Homogeneous particles
d. Heterogeneous particles
Answer  Explanation  Related Ques

ANSWER: Single rigid mass

Explanation:
No explanation is available for this question!


29)   Which of the following is not a hoisting equipment with lifting gear?

a. Cage elevators
b. Jib cranes
c. Pulleys
d. Troughed belts
Answer  Explanation  Related Ques

ANSWER: Troughed belts

Explanation:
No explanation is available for this question!


30)   Which of the following is a property of bulk load?

a. Hardness
b. Cake forming tendency
c. Suspension part
d. Weight
Answer  Explanation  Related Ques

ANSWER: Cake forming tendency

Explanation:
No explanation is available for this question!


31)   What are the factors affecting selection of casting process?

a. Tolerances
b. Surface finish
c. Both a. and b.
d. None of the above
Answer  Explanation  Related Ques

ANSWER: Both a. and b.

Explanation:
No explanation is available for this question!


32)   In forging process, forging plane is the plane __________

a. parallel to die motion
b. perpendicular to die motion
c. where two die halves meet
d. none of the above
Answer  Explanation  Related Ques

ANSWER: perpendicular to die motion

Explanation:
No explanation is available for this question!


33)   Which of the following processes is used for surface finishing?

a. Shaping
b. Broaching
c. Lapping
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Lapping

Explanation:
No explanation is available for this question!


34)   Which of the following statements is/are true about safety/risk?

a. Risk is potential for damage
b. Hazard is likely hood of damage
c. Danger is combination of risk and hazard
d. All of the above
Answer  Explanation  Related Ques

ANSWER: Danger is combination of risk and hazard

Explanation:
No explanation is available for this question!


35)   Which of the following ergonomic factors are encountered in engineering applications?

a. Thermal radiations
b. Lubrication failure
c. Fatigue
d. Corrosion
Answer  Explanation  Related Ques

ANSWER: Fatigue

Explanation:
No explanation is available for this question!