In a gear, having Involute teeth, the normal to the Involute is a tangent to the
Base circle
Pitch circle
Addendum circle
Dedendum circle
Correct Answer :
A. Base circle
Related Questions
The temperature required for full annealing in hypereutectoid steel is
50°C above upper critical temperature
50°C below upper critical temperature
50°C above lower critical temperature
50°C below lower critical temperature
The rated life of a bearing varies
Directly as load
Inversely as square of load
Inversely as cube of load
Inversely as fourth power of load
Two helical springs of the same material and of equal circular crosssection, length and number of turns, but having radii 80 mm and 40 mm, kept concentrically (smaller radius spring within the larger radius spring), are compressed between two parallel planes with a load W. The inner spring will carry a load equal to
W/2
2W/3
W/9
8W/9
Which of the following statement is correct, for two shafts connected in parallel?
Torque in each shaft is the same
Shear stress in each shaft is the same
Angle of twist of each shaft is the same
Torsional stiffness of each shaft is the same
The number of slots in a 25 mm castle nut is
8
6
4
2
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 steel containing 0.8% carbon is known as
Eutectoid steel
Hypereutectoid steel
Hypo-eutectoid steel
None of these
In radial bearings, the load acts __________ to the axis of rotation.
Parallel
Perpendicular
Both A and B
None of these
An elastic bar is fixed at the upper end and loaded at the lower end by a falling weight. The shock load produced can be reduced by
Increasing the length of bar
Decreasing the cross-sectional area of the bar
Decreasing the modulus of elasticity of the bar
All of the above
In a gear, having Involute teeth, the normal to the Involute is a tangent to the
Base circle
Pitch circle
Addendum circle
Dedendum circle
The maximum normal stress theory is used for
Plastic materials
Brittle materials
Non-ferrous materials
Ductile materials
The endurance or fatigue limit is defined as the maximum value of the stress which a polished standard specimen can withstand without failure, for infinite number of cycles, when subjected to
Static load
Dynamic load
Static as well as dynamic load
Completely reversed load
An alien bolt is
Self locking bolt
Same as stud
Provided with hexagonal depression in head
Used in high speed components
Maximum principal stress theory is applicable for
Ductile materials
Brittle materials
Elastic materials
All of the above
A tube has the following advantage over pipe
Lighter and easier to handle
Greater shock absorption
Smoother inside walls
All of the above
In a flat belt drive, if the slip between the driver and belt is 1 %, between the belt and follower is 3% and driver and follower pulley diameters are equal, then velocity ratio of the drive will be
0.96
0.97
0.98
0.99
Belt slip may occur due to
Heavy load
Loose belt
Driving pulley too small
All of the above
Which of the following spring is used in mechanical wrist watch?
Helical compression spring
Spiral spring
Torsion spring
Belleville spring
The piston rod of a steam engine is usually connected to the crosshead by means of
Bolted joint
Knuckle joint
Cotter joint
Universal joint
The cold working of metals is carried out __________ the recrystallisation temperature.
Above
Below
At
None of these
When a bolt is subjected to shock loading, the resilience of the bolt should be considered in order to prevent breakage at the
Thread
Middle
Shank
Head
Which of the following is a permanent fastening?
Bolts
Keys
Cotters
Rivets
An Involute pinion and gear are in mesh. If both have the same size of addendum, then there will be interference between the
Tip of the pinion and flank of gear
Tip of the gear and flank of pinion
Flanks of both gear and pinion
Tip of both gear and pinion
When bevel gears connect two shafts whose axes intersect at an angle greater than a right angle and one of the bevel gears has a pitch angle of 90°, then they are known as
Crown bevel gears
Angular bevel gears
Mitre gears
Internal bevel gears
In a belt drive, if the pulley diameter is doubled keeping the tension and belt width constant, then it will be necessary to
Increase the key length
Increase the key depth
Increase the key width
Decrease the key length
A taper key which fits half in the key way of the hub and half in the key way of shaft, is known as
Angular bevel gears
Mitre gears
Crown Bevel gears
Internal bevel gears
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
The groove angle of pulleys for V-belt is
340 to 360
420 to 450
More than 400
300 to 320
In the calculation of induced shear stress in helical springs, the Wahl's stress factor is used to take care of
Combined effect of transverse shear stress and bending stress in the wire
Combined effect of bending stress and curvature of the wire
Combined effect of transverse shear stress and curvature of wire
Combined effect of torsional shear stress and transverse shear stress in the wire
The stress in the threaded part of the bolt will be __________ as compared to the shank.
Same
Higher
Lower
None of these