The shock resistance of steel is increased by adding
Nickel
Chromium
Nickel and chromium
Cobalt and molybdenum
Correct Answer :
C. Nickel and chromium
Related Questions
The ball bearings are provided with a cage
To reduce friction
To facilitate slipping of balls
To prevent the lubricant from flowing out
To maintain the balls at a fixed distance apart
An open belt drive is used when
Shafts are arranged at right angles and rotate in one definite direction
Shafts are arranged parallel and rotate in the opposite directions
Shafts are arranged parallel and rotate in the same directions
Driven shaft is to be started or stopped whenever desired without interfering with the driving shaft
An alien bolt is
Self locking bolt
Same as stud
Provided with hexagonal depression in head
Used in high speed components
Two shafts will have equal strength, if
Diameter of both the shafts is same
Angle of twist of both the shafts is same
Material of both the shafts is same
Twisting moment of both the shafts is same
The usual clearance provided in hydrodynamic bearing per mm of diameter of shaft is
0.01 micron
0.1 micron
1 micron
10 microns
For a square key made of mild steel, the shear and crushing strength are related as
Shear strength is equal to crushing strength
Shear strength is greater than crushing strength
Shear strength is less than crushing strength
None of the above
According to Indian standards, total numbers of tolerance grades are
8
12
18
20
The shearing stresses in the inner face as compared to outer face of the wire in a heavy close coiled spring is
Larger
Smaller
Equal
Larger/smaller depending on diameter of spring coil
The load cup of a screw jack is made separate from the head of the spindle to
Prevent the rotation of load being lifted
Enhance the load carrying capacity of the jack
Reduce the effort needed for lifting the working load
Reduce the value of frictional torque
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 cyclic loading than the outer side
It is subjected to a higher stress 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
The resistance to fatigue of a material is measured by
Elastic limit
Ultimate tensile strength
Young's modulus
Endurance limit
The value of stress concentration factor depends upon
Material and geometry of the part
Geometry of the part
Material of the part
None of these
Jam nut is a locking device in which
One smaller nut is tightened over main nut and main nut tightened against smaller one by loosening, creating friction jamming
A slot is cut partly in middle of nut and then slot reduced by tightening a screw
A hard fibre or nylon cotter is recessed in the nut and becomes threaded as the nut is screwed on the bolt causing a tight grip
Through slots are made at top and a cotter pin is passed through these and a hole in the bolt, and cotter spitted and bent in reverse direction at other end
A locking device extensively used in marine type connecting rod ends is a
Jam nut
Castle nut
Sawn nut
Ring nut
A V-belt designated as B 4430 LP has
4430 mm as diameter of small pulley
4430 mm as nominal pitch length
4430 mm as diameter of large pulley
4430 mm as centre distance between pulleys
The velocity factor for very accurately cut and ground metallic gears operating at velocities upto __________ are equal to 6/(6 + v).
10 m/s
12.5 m/s
15 m/s
20 m/s
The design of the pressure vessel is based on
Longitudinal stress
Hoop stress
Longitudinal and hoop stress
None of these
According to Indian standards, total numbers of fundamental deviations are
10
15
20
25
Which of the following cotter joint will be used to connect strap end of a connecting rod?
Spigot and socket cotter joint
Sleeve and cotter joint
Gib and cotter joint
Any one of these
In worm gears, the pressure angle is ________ the angle between two inclined faces in axial plane.
Half
Twice
Thrice
None of these
The distribution of the forces along the length of key fitted in a shaft
Varies linearly
Is uniform throughout
Varies exponentially, being more near the torque-input end
Varies exponentially, being less near the torque-input end
Tensile strength of a mild steel specimen can be roughly predicted from following hardness test
Brinell
Rockwell
Vickers
None of the above
The crest diameter of a screw thread is same as
Major diameter
Minor diameter
Pitch diameter
Core diameter
When a close coiled helical spring is compressed, its wire is subjected to
Tension
Shear
Compression
All of the above
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
The bending moment M and a torque T is applied on a solid circular shaft. If the maximum bending stress equals to maximum shear stress developed, then M is equal to
T/2
T
2T
4T
The plasticity is the property of a material which enables it to
Regain its original shape after deformation when the external forces are removed
Draw into wires by the application of a tensile force
Resist fracture due to high impact loads
Retain deformation produced under load permanently
The temperature at which the new grains are formed in the metal is known as
Lower critical temperature
Upper critical temperature
Recrystallisation temperature
None of these
In case of pressure vessels having closed ends, the fluid pressure induces
Longitudinal stress
Shear stress
Circumferential stress
None of these
In the levers of third type, the mechanical advantage is __________ one.
Less than
Equal to
More than
None of these