Q.1

According to Indian standard specifications,H6/g5 means that the

  • actual size is 100 mm
  • basic size is 100 mm
  • difference between the actual size and basic size is 100 mm
  • none of the above
Q.2

A screw will be self locking, if

  • friction angle is less than helix angle
  • friction angle is more than helix angle
  • friction angle is equal to helix angle
  • efficiency of screw is 100%
Q.3

In helical gears, the right hand helixes on one gear will mesh __________ helixes on the other gear.

  • right hand
  • left hand
Q.4

The value of stress concentration factor depends upon

  • material of the part
  • geometry of the part
  • material and geometry of the part
  • none of these
Q.5

In a flange coupling, the thickness of flanges is taken as one-half the diameter of shaft.

  • Agree
  • Disagree
Q.6

A screw will be self locking, if

  • friction angle is less than helix angle
  • friction angle is more than helix angle
  • friction angle is equal to helix angle
  • efficiency of screw is 100%
Q.7

The resistance to fatigue of a material is measured by

  • elastic limit
  • Young's modulus
  • ultimate tensile strength
  • endurance limit
Q.8

The bell crank levers used in railway signalling arrangement are of third type levers.

  • True
  • False
Q.9

When a nut is tightened by placing a washer below it, the bolt will be subjected to

  • tensile stress
  • compressive stress
  • shear stress
  • none of these
Q.10

In an ordinary bolt, the effect of the impulsive loads applied axially is concentrated on the cross-sectional area at the root of the threads.

  • Yes
  • No
Q.11

The endurance limit for a mirror polished material will be __________ as compared to unpolished material.

  • same
  • less
  • more
Q.12

The surface finish factor for a mirror polished material is

  • 0.45
  • 0.65
  • 0.85
  • 1
Q.13

A connecting rod is four times strong in buckling about Y-axis than about X-axis.

  • Agree
  • Disagree
Q.14

The rivet head used for boiler plate riveting is usually

  • snap head
  • pan head
  • counter sunk head
  • conical head
Q.15

The taper on cotter varies from

  • 1 in l5 to 1 in 10
  • 1 in 24 to 1 in 20
  • 1 in 32 to 1 in 24
  • 1 in 48 to 1 in 24
Q.16

A connecting rod is designed as a

  • long column
  • short column
  • strut
  • all of these
Q.17

For unequal width of butt straps, the thickness of butt straps are

  • 0.75 t for wide strap on the inside and 0.625 t for narrow strap on the outside
  • 0.75 t for narrow strap on the inside and 0.625 t for wide strap on the outside
  • 0.75 t for both the straps on the inside and outside
  • 0.625 t for both the straps on the inside and outside
Q.18

The maximum shear stress theory is used for

  • brittle materials
  • ductile materials
  • plastic materials
  • non-ferrous materials
Q.19

When spring index increases, the value of Wahl's stress factor

  • increases linearly
  • decreases linearly
  • remains same
  • increases exponentially
Q.20

According to I.B.R., shearing resistance required to shear off the rivet per pitch length (in double shear) is (where n = Number of rivets per pitch length)

  • d2 x τ x n
  • 1.875 x d2 x τ x n
  • 2 x d2 x τ x n
  • 3 x d2x τ x n
Q.21

A locking device extensively used in marine type connecting rod ends is a

  • jam nut
  • castle nut
  • sawn nut
  • ring nut
Q.22

A metal pipe of 1 m diameter contains a fluid having a pressure of 1 N/mm2. If the permissible tensile stress in the metal isN/mm2, then the thickness of the metal required for making the pipe will be

  • 5 mm
  • 10 mm
  • 15 mm
  • 25 mm
Q.23

When bevel gears having equal teeth and equal pitch angles connect two shafts whose axes intersect at right angle, then they are known as

  • angular bevel gears
  • crown bevel gears
  • internal bevel gears
  • mitre gears
Q.24

The radial distance of a tooth from the pitch circle to the top of the tooth is called

  • dedendum
  • addendum
  • clearance
  • working depth
Q.25

A localised compressive stress at the area of contact between two members is known as

  • tensile stress
  • bending stress
  • bearing stress
  • shear stress
Q.26

The ratio of endurance limit in shear to the endurance limit in flexure is

  • 0.25
  • 0.40
  • 0.55
  • 0.70
Q.27

When two helical springs of equal lengths are arranged to form a cluster spring, then

  • shear stress in each spring will be equal
  • load taken by each spring will be half the total load
  • all of the above
  • none of these
Q.28

A sliding bearing which operates without any lubricant present, is called

  • zero film bearing
  • boundary lubricated bearing
  • hydrodynamic lubricated bearing
  • hydrostatic lubricated bearing
Q.29

For low and moderate speed engines, the cam follower should move with

  • uniform velocity
  • simple harmonic motion
  • uniform accleration and retardation
  • cycloidal motion
Q.30

The cracks in helical springs used in railway carriages usually start on the inner side of the coil because of the fact that

  • it is subjected to a higher stress than the outer side
  • it is subjected to a higher cyclic loading than the outer side
  • it is more stretched than the outer side during the manufacturing process
  • it has a lower curvature than the outer side
Q.31

The period during which the cam follower remains at rest, when cam moves, is known as

  • constant period
  • fixed period
  • dwell period
  • idle period
Q.32

In designing a sleeve coupling, length of the sleeve is taken as (where d = Diameter of the shaft)

  • d + 17 mm
  • 2 d + 13 mm
  • 2 d + 20 mm
  • 3.5 d
Q.33

A single strap butt joint is always in __________ shear.

  • single
  • double
Q.34

The cracks in helical springs used in railway carriages usually start on the inner side of the coil because of the fact that

  • it is subjected to a higher stress than the outer side
  • it is subjected to a higher cyclic loading than the outer side
  • it is more stretched than the outer side during the manufacturing process
  • it has a lower curvature than the outer side
Q.35

Which of the following screw thread is used for power transmission in one direction only.

  • Acme threads
  • Square threads
  • Buttress threads
  • Multiple threads
Q.36

The cross-section of the arm of a bell crank lever is

  • rectangular
  • elliptical
  • I-section
  • any one of these
Q.37

The period during which the cam follower remains at rest, when cam moves, is known as

  • constant period
  • fixed period
  • dwell period
  • idle period
Q.38

A plate with an elliptical hole in the centre, with semi-major axis (a) perpendicular to the direction of loading and semi-minor axis (b) along the direction of loading, is subjected to a pull P. The maximum stress induced at the edge of the hole is equal to (where σ = Stress for a plate with no hole i.e. nominal stress)

Q.39

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

  • Agree
  • Disagree
Q.40

When the speed of belt increases,

  • the coefficient of friction between the belt and pulley increases
  • the coefficient of friction between the belt and pulley decreases
  • the power transmitted will decrease
  • the power transmitted will increase
Q.41

A sliding bearing which can support steady loads without any relative motion between the journal and the bearing, is called

  • zero film bearing
  • boundary lubricated bearing
  • hydrodynamic lubricated bearing
  • hydrostatic lubricated bearing
Q.42

In a gear, having involute teeth, the normal to the involute is a tangent to the

  • pitch circle
  • base circle
  • addendum circle
  • dedendum circle
Q.43

The metal suitable for bearings subjected to heavy loads is

  • silicon bronze
  • white metal
  • monel metal
  • phosphor bronze
Q.44

The lower deviation is the algebraic difference between the

  • minimum limit and the basic size
  • maximum limit and the basic size
  • actual size and the corresponding basic size
  • none of the above
Q.45

For a shaft diameter ofmm, the number of bolts in a marine flange coupling should be

  • 4
  • 6
  • 8
  • 10
Q.46

The material used for brake lining should have __________ coefficient of friction.

  • low
  • high
Q.47

Euler's formula for a mild steel column is not valid if the slenderness ratio is

  • 60
  • 90
  • 100
  • 120
Q.48

According to Indian standards, a bolt thread of 6 mm size of coarse pitch and with allowance on the threads and normal tolerance grade is designated as

  • M6
  • M8
  • M6 - 8d
  • M8 - 6d
Q.49

A tapered key which fits in a key way in the hub and the bottom of which is shaped to fit the curved surface of the shaft, is known as hollow saddle key.

  • Correct
  • Incorrect
Q.50

Which of the following statement is correct ?

  • A parallel sunk key is a taperless key
  • A parallel sunk key may be rectangular or square in cross-section
  • A flat saddle key is a taper key which fits in a key way of the hub and is flat on the shaft
  • all of the above
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