Deck 5: Mechanical Engineering: V-Belts, Gears, Chains

Question 1

In case of V-belts

A)Belts should not touch the bottom of groove in pulley
B)Belts should touch the bottom of groove in pulley
C)Grooves in pulley are generally wider than the belt
D)Tension in belt remains constant throughout
E)The efficiency of transmission is less

Answer 1

Belts should touch the bottom of groove in pulley

Question 2

According to the law of gearing

A)Clearance should be minimum 0.15 mm
B)Teeth should be cycloidal type
C)Common normal at the point of contact always passes through a fixed point (pitch point) on the line joining the centres of rotation
D)The gears whould be cut with the cutter having same module
E)Teeth should be involute type

Answer 2

Common normal at the point of contact always passes through a fixed point (pitch point) on the line joining the centres of rotation

Question 3

In a V-belt having B section may be used when the load to be transmitted is

A)60-75 HP
B)3 to 20 HP
C)30-60 HP
D)75-90 HP
E)100 HP

Answer 3

3 to 20 HP

Question 4

A slider crank chain consists of

A)One turning and two sliding pairs
B)Two turning and one sliding pair
C)Three turning and one sliding pairs
D)One turning and one sliding pair
E)Two turning and two aliding pairs

Question 5

In case of reciprocating engines the primary forces

A)Are fully balanced
B)Remain unbalanced
C)Are partially balanced
D)Cannot be balanced
E)None of the above

Question 6

Which one of the following is a transmission type dynamometer?

A)Prony brake
B)Rope brake
C)Hydraulic dynamometer
D)Electric generator types
E)None of the above

Question 7

The rectilinear motion of a piston is converted into rotary motion by

A)Cross-head
B)Piston pin
C)Connecting rod
D)Crank
E)Piston rod

Question 8

In case of gears the pressure angle is

A)The angle between the line of action and the common tangent to the pitch surface in the plane of rotation
B)The angle between the normal to the point of contact and the shaft axis
C)The angle between the normal to dedendum at the path point and tangent to the dedendum at the path point and tangent to the dedendum at the same point
D)The angle of obliquity between the tangent drawn at the point of contact of the two mating gears
E)None of the above

Question 9

A swinging pendulum in its mid-position possesses

A)only the potential energy
B)only the kinetic energy
C)more kinetic energy and less potential energy
D)None of the above
E)None of the above.

Question 10

When the two elements of a pair are kept in contact with the help of a spring, the pair is known as

A)A lower pair
B)a higher pair
C)a closed pair
D)an unclosed pair
E)None of the above

Question 11

Which one of the following is a higher pair?

A)Tooth gearing mechanism
B)Thomoson indicator mechanism
C)Crossby indicator mechanism
D)Double McInnes Indicator mechanism
E)Hart's straight line mechanism

Question 12

The difference between a machine and a structure is

A)The machine serves to modify and transmit forces only whereas structures serve to modify and transmit mechanical work
B)The machine serves to modify and transmit mechanical work whereas structures serve to modify and transmit forces only
C)The relative motion exists between the parts of a structures whereas it does not exist in machines
D)Structures are temporary constructions whereas machines are paramanent
E)None of the above

Question 13

In case of lower pairs

A)There is surface contact between the two elements while in the motion
B)There is line contact between the two elements while in the motion
C)There is point contact between the two elements while is motion
D)The contact is only at lower end of the two elements while in motion
E)None of the above

Question 14

A 0.5 kg weight attached to a light spring elongates it 0.6 mm. The natural frequency of the system should be approximately

A)6 Hz
B)26 Hz
C)36 Hz
D)32 Hz
E)16 Hz

Question 15

A piston and cylinder in a slider crank mechanism form a

A)Sliding pair
B)Rolling pair
C)Cylindrical pair.
D)Sliding pair.
E)Turning pair

Question 16

In case of reciprocating engine mechanism

A)The primary and secondary forces have same direction
B)The primary and secondary forces have same amplitude
C)The ratio of magnitude of primary forces of secondary forces is 2
D)The primary force has twoce the frequency of secondary force
E)None of the above

Question 17

At node of the shaft

A)The vibrations are inimum
B)The vibrations are maximum
C)The vibrations are average
D)The vibrations are zero
E)None of the above

Question 18

In a well greased ball bearing the coefficient of friction may be in the range

A)0.45 to 0.60
B)0.25 to 0.45
C)0.60 to 0.70
D)0.70 to 0.80
E)0.1 to 0.25

Question 19

A vibrating system with unity as damping factor will be

A)Free from vibrations
B)Damped to 1% of critical speed
C)Damped to safe limits
D)Partly damped
E)Critically damped

Question 20

In case of spur gears the flank of the tooth is

A)The surface of the top of the tooth
B)The part of the tooth surface lying below the pitch surface
C)The curve forming face and flank
D)Radius that connects in the root circle to the profile of the tooth
E)The width of the gear tooth measured axially along the pitch surface

Question 21

The number of links in a pantograph is equal to

A)3
B)4
C)5
D)7
E)6

Question 22

Module is expressed in

A)mm
B)mm/mm
C)mm/No. of teeth
D)Dimensionless
E)None of the above

Question 23

In case of an elliptical trammel

A)One pair turns and three pairs slide
B)All four pairs slide
C)Three pairs turn and one pair slides
D)All four pairs turn
E)Two pairs turn and two pairs slide

Question 24

Creep in belts is due to

A)Plasticity of belt material
B)Elasticity of belt material
C)Plastic deformation of belt material due to constant use
D)Differential elougation of belt due to difference in tension on two sides of a pulley
E)Elongation of belt due to tension