If two springs are in parallel then their overall stiffness will be
Half
Same
Double
None of the above
Correct Answer :
C. Double
Related Questions
A steel containing upto 0.15% carbon is known as
Mild steel
Dead mild steel
Medium carbon steel
High carbon steel
Which of the following formula is used in designing a connecting rod?
Euler's formula
Rankine's formula
Johnson's straight line formula
Johnson's parabolic formula
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)
(π/4) d² × τ × n
1.875 × (π/4) d² × τ × n
2 × (π/4) d² × τ × n
3 × (π/4) d² × τ × n
While designing a screw in a screw jack against buckling failure, the end conditions for the screw are taken as
Both the ends fixed
Both the ends hinged
One end fixed and the other end hinged
One end fixed and the other end free
When two non-parallel or intersecting but coplanar shafts are connected by gears, the arrangement is known as,
Bevel gearing
Helical gearing
Worm gearing
None of these
When carbon in the cast iron is principally in the form of graphite, the cast iron will be of
Brown colour
Yellow colour
White colour
Grey colour
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 is 20 N/mm², then the thickness of the metal required for making the pipe will be
5 mm
10 mm
15 mm
25 mm
In order to have a connecting rod equally strong in buckling about X-axis and Y-axis, the moment of inertia about X-axis should be __________ the moment of inertia about Y-axis.
Equal to
Twice
Three times
Four times
Eulers formula for a mild steel column is not valid if the slenderness ratio is
90
60
120
100
The material commonly used for crane hooks is
Cast iron
Wrought iron
Mild steel
Aluminium
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
Hollow key
Soft key
None of these
The property of a material which enables it to resist fracture due to high impact loads is known as
Elasticity
Endurance
Strength
Toughness
Transverse fillet welded joints are designed for
Tensile strength
Compressive strength
Shear strength
Bending strength
Two rigid plates are clamped by means of bolt and nut with an initial force F. After tightening, a separating force P (P < F) is applied to the lower plate, which in turn acts on the nut. The tension in the both after this is
F + P
F P
P
F
If shearing stress in nut is half the tensile stress in a bolt, then nut length should be equal to
Diameter of bolt
0.75 × diameter of bolt
1.25 × diameter of bolt
1.5 × diameter of bolt
A bolt is designed on the basis of __________ with a large factor of safety.
Direct tensile stress
Direct compressive stress
Direct bending stress
Direct shear stress
For a shaft diameter of 100 mm, the number of bolts in a flange coupling should be
4
6
8
10
Two shafts of the same length and material are joined in series. If the ratio of their diameters is 2, then the ratio of their angles of twist will be
2
4
8
16
A self locking screw has
Fine threads
Course threads
Coefficient of friction is greater than tangent of load angle
Hole for inserting split pin
Basic hole is one
Whose upper deviation is zero
Whose lower deviation is zero
Whose lower as well as upper deviations are zero
Does not exist
If a load W is applied instantaneously on a bar; Then the stress induced in bar will
Be independent of ratio of mass of load W to mass of bar (y)
Increase with increase in y
Decrease with decrease in y
Depend on other considerations
A key capable of tilting in a recess milled out in a shaft is known as
Woodruff key
Feather key
Flat saddle key
Hollow saddle key
The difference between the tooth space and the tooth thickness as measured on the pitch circle, is called
Working depth
Clearance
Backlash
Face width
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
A screw is said to be over hauling screw, if the
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%
According to Indian standards, total numbers of tolerance grades are
8
12
18
20
In a partial journal bearing, the angle of contact of the bearing with the journal is
120°
180°
270°
360°
In most machine members, the damping capacity of the material should be
Low
Zero
High
Could be anything
Belt slip may occur due to
Heavy load
Loose belt
Driving pulley too small
All of the above
Fabric belts are used in industrial applications because
They are cheap
They can work at high temperature
They are unaffected by moisture and humidity
None of the above