Which of the following material has the maximum ductility?
Copper
Mild steel
Aluminium
Zinc
Correct Answer :
B. Mild steel
Related Questions
In worm gears, the angle between the tangent to the pitch helix and an element of the cylinder, is known as
Helix angle
Pressure angle
Pitch lead angle
None of these
A special case of ductility which permits materials to be rolled or hammered into thin sheets, is called
Plasticity
Elasticity
Ductility
Malleability
Resilience of a material is important, when it is subjected to
Combined loading
Fatigue
Thermal stresses
Shock loading
The objective of caulking in a riveted joint is to make the joint
Free from corrosion
Stronger in tension
Free from stress
Leak-proof
In the levers of third type, the mechanical advantage is __________ one.
Less than
Equal to
More than
None of these
The creep in the belt is due to
Effect of temperature on belt
Material of belt
Unequal extensions in the belt due to tight and slack side tensions
Stresses beyond elastic limit of belt material
Which of the following statement is wrong?
The pitch of rivets is obtained by equating the tearing resistance of the plate to the shearing resistance of the rivets
The pitch of rivets should not be less than 2d, where d is the diameter of rivet hole
The maximum value of the pitch of rivets for a longitudinal joint of a boiler, as per I.B.R., is given by Pmax = C.t + 41.28 mm
According to I.B.R., the thickness of butt strap shall not be less than 5 mm
The draw of cotter should not be more than
3 mm
6 mm
8 mm
12 mm
Fibrous fracture occurs in
Ductile material
Brittle material
Elastic material
Hard material
If T is the actual number of teeth on a helical gear and φ is the helix angle for the teeth, then formative number of teeth is written as
T sec3φ
T sec²φ
T/sec3φ
T cosecφ
The suitable material for belt in agricultural machinery is
Leather
Rubber
Cotton duck
Balata gum
Cast iron pipes are mainly used
For conveying steam
In water and sewage systems
In pressure lubrication systems on prime movers
All of the above
The taper on key is given on
Bottom side only
Top side only
On both sides
Any side
In order to permit the thermal expansion/contraction of tubing, it should be
Crimped
Honed
Flared
Bent
The bearings of heavy series have capacity ________ over the medium series.
20 to 30%
10 to 20%
30 to 40%
40 to 50%
Coaxing is the procedure of increasing
Metal strength by cycling
Metal hardness by surface treatment
Metal resistance to corrosion by coating
Fatigue limit by overstressing the metal by successively increasing loadings
The size of a cam depends upon
Base circle
Pitch circle
Prime circle
Pitch curve
According to I.B.R., the factor of safety of riveted joint should not be less than
1
2
3
4
The square threads are usually found on
Spindles of bench vices
Railway carriage couplings
Feed mechanism of machine tools
Screw cutting lathes
According to Rankine's theory, the failure occurs at a point in a member
When the maximum shear stress in a biaxial stress system reaches the shear stress at elastic limit in a simple tension test
When the maximum principal stress in a biaxial stress system reaches the elastic limit of the material in a simple tension test
When the strain energy per unit volume in a biaxial stress system reaches the strain energy at the elastic limit per unit volume as determined from a simple tension test
When the maximum principal strain in a biaxial stress system reaches the strain at the elastic limit as determined from a simple tension test
A triple riveted butt joint with double straps of unequal width is to be designed for a boiler shell. The pitch of the rivets in the outer row is double the pitch in the inner row and zigzag riveting is proposed. Which of the following statement is correct?
There are four rivets per pitch length, all in double shear
There are four rivets per pitch length, out of which two are in single shear and two are in double shear
There are five rivets per pitch length, all in double shear
There are five rivets per pitch length, out of which four are in double shear and one is in single shear
Slenderness ratio is the ratio of
Effective length of column to least radius of gyration of the column
Width of column to depth of column
Maximum size of column to minimum size of column
Effective length of column to width of column
A crankshaft is a __________ shaft.
Transmission
Machine
Machine frame
None of these
Whether any core is required in wire ropes
Yes
No
Sometimes
Rarely
The sleeve or muff coupling is designed as a
Dun cylinder
Hollow shaft
Solid shaft
Thick cylinder
Belt slip may occur due to
Heavy load
Loose belt
Driving pulley too small
All of the above
In cylindrical cams, the follower moves
In a direction perpendicular to the cam axis
In a direction parallel to the cam axis
In any direction irrespective of cam axis
Along the cam axis
According to Indian standards, total numbers of tolerance grades are
8
12
18
20
The objective of crowning of the flat pulleys of belt drive is to
Prevent the belt from running off the pulley
Increase the power transmission capacity
Increase the belt velocity
Prevent the belt joint from damaging the belt surface
Which is correct statement? Stress concentration in cyclic loading is
Very serious in brittle materials and less serious in ductile materials
Very serious in ductile materials and less serious in brittle materials
Equally serious in both types of materials
Seriousness would depend on other factors