Question Set 197

11. 

Antifriction bearings are

A.

thick lubricated bearings

B.

plastic bearings

C.

thin lubricated bearings

D.

ball and roller bearings

Answer: Option D

 

12. 

Stress concentration factor is defined as the ratio of

A.

maximum stress to the endurance limit

B.

nominal stress to the enurance limit

C.

maximum stress to the nominal stress

D.

nominal stress to the maximum stress

Answer: Option C

 

13. 

The property of a bearing material which has the ability to accomodate shaft deflections and bearing inaccuracies by plastic deformation without excessive wear and heating, is known as

A.

bondability

B.

embeddability

C.

comformability

D.

fatigue strength

Answer: Option C

 

14. 

In the levers of __________ type, the mechanical advantage is less than one.

A.

first

B.

second

C.

third

Answer: Option C

 

15. 

A hollow saddle key is

A.

a taper key which fits half in the key way of hub and half in the key way of shaft

B.

a taper key which fits in a key way of the hub and is flat on the shaft

C.

a taper key which fits in a key way of the hub and the bottom of the key is shaped to fit the curved surface of the shaft

D.

provided in pairs at right angles and each key is to withstand torsion in one direction only

Answer: Option C

 

16. 

A special case of ductility which permits materials to be rolled or hammered into thin sheets, is called

A.

plasticity

B.

elasticity

C.

ductility

D.

malleability

Answer: Option D

 

17. 

Crowning on pulley helps

A.

in decreasing the slip of the belt

B.

in increasing the slip of the belt

C.

to keep the belt in centre on a pulley while it is in motion

D.

to increase pulley life

Answer: Option C

 

18. 

The temperature required for full annealing in hyper-eutectoid steel is

A.

50°C above upper critical temperature

B.

50°C below upper critical temperature

C.

50°C above lower critical temperature

D.

50°C below lower critical temperature

Answer: Option C

19. 

The effect of key ways on a shaft is to reduce its load carrying capacity and to increase its torsional rigidity.

A.

True

B.

False

Answer: Option B

 

20. 

The efficiency of a riveted joint is equal to

A.

Pt/P

B.

Ps/P

C.

Pc/P

D.

least of Pt, Ps and Pc/P

Answer: Option D