The ratio of circumferential stress to longitudinal stress in a thin cylinder subjected to an internal pressure is
½
1
2
4
Correct Answer :
C. 2
Related Questions
Elastic nut is a locking device in which
One small 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
Hard fibre or nylon cotter is recessed in the nut and becomes threaded as the nut is stewed 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 pin splitted and bent in reverse direction at other end
The shock absorbing capacity of a bolt can be increased by
Tightening it properly
Increasing shank diameter
Grinding the shank
Making shank diameter equal to core diameter of thread.
In order to permit the thermal expansion/contraction of tubing, it should be
Crimped
Honed
Flared
Bent
The radial distance of a tooth from the pitch circle to the top of the tooth is called
Addendum
Dedendum
Clearance
Working depth
According to maximum shear stress theory, the maximum shear stress in the shaft is
(1/2) × √(σ² + 4τ²)
√(σ² + 4τ²)
(1/2) × [σ + √(σ² + 4τ²)]
σ + √(σ² + 4τ²)
The piston rod of a steam engine is usually connected to the crosshead by means of
Bolted joint
Knuckle joint
Cotter joint
Universal joint
A sliding bearing which can support steady loads without any relative motion between the journal and the bearing, is called
Hydrostatic lubricated bearing
Hydrodynamic lubricated bearing
Boundary lubricated bearing
Zero film bearing
The process which improves the machinability of steels, but lowers the hardness and tensile strength is
Normalising
Full annealing
Process annealing
Spheroidising
The allowable static stress for steel gears is approximately __________ of the ultimate tensile stress.
One-fourth
One-third
One-half
Double
The stress which vary from a minimum value to a maximum value of the same nature (i.e. tensile or compressive) is called
Repeated stress
Yield stress
Fluctuating stress
Alternating stress
According to Indian standards, total numbers of tolerance grades are
8
12
18
20
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 rolling contact bearings are known as
Thick lubricated bearings
Plastic bearings
Antifriction bearings
Thin lubricated bearings
When the screw in a mechanical screw jack rotates, the load kept on the top of it moves
Axially upwards
Axially downwards
Axially upwards or downwards
None of these
Machine screws are
Similar to small size tap bolts except that a greater variety of shapes of heads are available
Slotted for a screw driver and generally used with a nut
Used to prevent relative motion between two parts
Similar to stud
The taper on a rectangular sunk key is
1 in 16
1 in 32
1 in 48
1 in 100
In levers, leverage is the ratio of
Load lifted to the effort applied
Mechanical advantage to the velocity ratio
Load arm to the effort arm
Effort arm to the load arm
In helical gears, the distance parallel to the axis, between similar faces of adjacent teeth, is called
Normal pitch
Axial pitch
Diametral pitch
Module
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
The speed of the sprocket reduces as the chain pitch __________ for a given number of teeth.
Increases
Decreases
Remain same
None of these
A spring of stiffness 1000 N/m is stretched initially by 100 mm from the undeformed position. The work required to stretch it by another 100 mm is
5 N-m
7 N-m
10 N-m
15 N-m
Which one of the following loading is considered for the design of axles?
Bending moment only
Twisting moment only
Combined bending moment and twisting moments
Combined action of bending moment, twisting moment and axial thrust
Belt slip may occur due to
Heavy load
Loose belt
Driving pulley too small
All of the above
Which of the following statement is wrong?
A key is used as a temporary fastening
A key is subjected to tensile stresses
A key is always inserted parallel to the axis of the shaft
A key prevents relative motion between the shaft and boss of the pulley
Set screws are
Similar to small size tap bolts except that a greater variety of shapes of heads are available
Slotted for a screw driver and generally used with a nut
Used to prevent relative motion between parts
Similar to stud
A connecting rod subjected to an axial load may buckle with
X-axis as neutral axis
Y-axis as neutral axis
X-axis or Y-axis as neutral axis
Z-axis
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
The expression 0.175 - 0.841/T is the Lewis form factor for
14 ½° composite and full depth involute system
20° full depth involute system
20° stub system
None of the above
A crankshaft is a __________ shaft.
Transmission
Machine
Machine frame
None of these
Which of the following statement is wrong?
The V-belt may be operated in either direction with tight side of the belt at the top or bottom
The V-belt drive is used with large centre distance
The power transmitted by V-belts is less than flat belts for the same coefficient of friction, arc of contact and allowable tension in the belts
The ratio of driving tensions in V-belt drive is more than flat belt drives