Machine Design MCQs

Question 1

If the tearing efficiency of a riveted joint is 75%, then the ratio of diameter of rivet to the pitch is equal to

Accepted Answer

0.25

Answer

0.20

Answer

0.50

Answer

0.60

Question 2

Jam nut is a locking device in which

Accepted Answer

One smaller nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming

Answer

A slot is cut partly in middle of nut and then skit reduced by tightening a screw

Answer

A hard fiber or nylon cotter is recessed in the nut and becomes threaded as the nut is screwed on the bolt causing a tight grip

Answer

Through slots are made at top and a cotter-pin is passed through these and a hole in the bolt, and cotter splitted and bent in reverse direction at other end

Question 3

The pitch of threads on a lock nut in comparison to pitch of nut is

Accepted Answer

Same

Answer

Coarser

Answer

Finer

Answer

Very coarse

Question 4

Buttress threads are usually found on

Accepted Answer

Railway carriage couplings

Answer

Screw cutting lathes

Answer

Spindles of bench vices

Answer

Screw jack

Question 5

In order to obtain bolt of uniform strength

Accepted Answer

Drill an axial hole through head upto threaded portion so that shank area is equal to root area of thread

Answer

Increase shank diameter

Answer

Increase its length

Answer

Tighten the bolt properly

Question 6

A key capable of tilting in a recess milled out in a shaft is known as

Accepted Answer

Wood-ruff key

Answer

Feather key

Answer

Flat saddle key

Answer

Gib head key

Question 7

A key made from a cylindrical disc having segmental cross-section, is known as

Accepted Answer

Wood-ruff key

Answer

Feather key

Answer

Flat saddle key

Answer

Gib head key

Question 8

Turn buckle has

Accepted Answer

Left hand threads on one end and right hand threads on other end

Answer

Right hand threads on both ends

Answer

Left hand threads on both ends

Answer

No threads

Question 9

Elastic nut is a locking device in which

Accepted Answer

Hard fibre or nylon cotter is recessed in the nut and becomes threaded as the nut is srewed on the bolt causing a tight grip

Answer

One small nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming

Answer

A slot is cut partly in middle of nut and then slot reduced by tightening a screw

Answer

Through slots are made at top and a cotter-pin is passed through these and a hole in the bolt, and cotter pin splitted and bent in reverse direction at other end