Machine Design Questions and Answers Part-17

1. If a fastener is threaded into a tapped hole, then the fastener is likely to be called as
a) Screw
b) Bolt
c) Washer
d) Screw or bolt

Answer: a
Explanation: Bolt is threaded into a nut while screw is threaded into a tapped hole.

2. In nut and bolt fastener, nut is generally held stationary while bolt is rotated.
a) True
b) False

Answer: b
Explanation: Bolt is always held stationary while nut is rotated.

3. Which of the following is not a function of washer?
a) Distributes load over a large area of clamped parts
b) Provides bearing surface over large clearance bolts
c) Prevents marring of the bolt head and nut surface
d) Helps in locking of the fastener

Answer: d
Explanation: Washer doesn’t help in locking of fasteners.

4. Shank is the portion of bolt between the head and the thread.
a) True
b) False

Answer: a
Explanation: Shank is the portion between head and the thread of the bolt.

5. If there is no place to accommodate the nut, then one would choose the
a) Through Bolts
b) Tap Bolts
c) Studs
d) None of the mentioned

Answer: b
Explanation: Tap bolts are directly threaded into the clamped parts and does not require any nut.

6. Which of the following are good for parts that are seldom dismantled.
a) Through Bolts
b) Tap Bolts
c) Studs
d) Cannot be stated

Answer: b
Explanation: Tap bolts, if removed frequently will leave the threads in the part worn out and hence are used where dismantling is rare.

7. Which of the following requires more space for the rotation of spanner?
a) Square Head
b) Hexagonal Head
c) Both require equal space of rotation
d) Cannot be stated

Answer: a
Explanation: Angle of rotation for hexagonal head is one sixth of a revolution to enable the next pair of flats to be engaged while it is one fourth of a revolution in case of square head.

8. Fillister, button, flat and hexagonal heads are all tightened externally.
a) True
b) False

Answer: b
Explanation: All of these are internal drive screws having a slot for the screw driver of different shape on the head.

9. Set screws are subjected to tensile forces only.
a) Yes
b) No, they are subjected to compressive forces only
c) Both compressive and tensile
d) Can’t be determined

Answer: b
Explanation: Set screws are subjected to compressive forces only.

10. If the lateral force acting on the set screw is large and tends to displace one part with respect to other than which point is recommended?
a) Dog Point
b) Cone Point
c) Window Point
d) Cut Point

Answer: a
Explanation: Dog point is used when the lateral force is large provided the part has sufficient thickness to accommodate a cylindrical hole for dog point.