480 Important Theory of Machines MCQ Question and Answer | PDF Free Download
1.The natural frequency of free transverse vibrations due to uniformly distributed load acting over a simply supported shaft is (where δS = Static deflection of simply supported shaft due to uniformly distributed load)
- A0.4985/ √δS
- B0.5615/ √δS
- C0.571/ √δS
- D0.6253/ √δS
2.The working depth of a gear is the radial distance from the
- APitch circle to the bottom of a tooth
- BPitch circle to the top of a tooth
- CTop of a tooth to the bottom of a tooth
- DAddendum circle to the clearance circle
3.When the radius of rotation of balls __________ as the equilibrium speed increases, the governor is said to be unstable.
- ARemains constant
- BDecreases
- CIncreases
- DNone of these
4.A motor car moving at a certain speed takes a left turn in a curved path. If the engine rotates in the same direction as that of wheels, men due to centrifugal force
- AThe reaction on me inner wheels increases and on the outer wheels decreases
- BThe reaction on the outer wheels increases and on the inner wheels decreases
- CThe reaction on the front wheels increases and on the rear wheels decreases
- DThe reaction on the rear wheels increases and on the front wheels decreases
5.The unbalanced primary forces in a reciprocating engine are
- ABalanced completely
- BBalanced partially
- CBalanced by secondary forces
- DNot balanced
6.Carnot cycle is
- Aa reversible cycle
- Ban irreversible cycle
- Ca semi-reversible cycle
- Da quasi static cycle
7.Elements of pairs held together mechanically is known as
- AClosed pair
- BOpen pair
- CMechanical pair
- DRolling pair
8.A pulley and belt in a belt drive form a
- ACylindrical pair
- BTurning pair
- CRolling pair
- DSliding pair
9.In a multiple V-belt drive, when a single belt is damaged, it is preferable to change the complete set to
- AReduce vibration
- BReduce slip
- CEnsure uniform loading
- DEnsure proper alignment
10.The bearing used in railway axle boxes is
- ADeep groove ball bearing
- BDouble row self aligning ball bearing
- CDouble row spherical roller bearing
- DCylindrical roller bearing
11.Minimum number of teeth for involute rack and pinion arrangement for pressure angle of 20° is
- A10
- B20
- C30
- D40
12.The tractive force is maximum or minimum when the angle of inclination of crank with the line of stroke (θ) is equal to
- A0° and 90°
- B90° and 180°
- C135° and 315°
- D270° and 360°
13.The swaying couple is maximum or minimum when the angle of inclination of the crank to the line of stroke (θ) is equal to
- A90° and 180°
- B45° and 225°
- C180° and 270°
- D270° and 360°
14.A shaft has two heavy rotors mounted on it. The transverse natural frequencies, considering each of the rotor separately, are 100 Hz and 200 Hz respectively. The lowest critical speed is
- A5,367 r.p.m.
- B6,000 r.p.m.
- C9,360 r.p.m.
- D12,000 r.p.m.
15.A spring controlled governor is said to be unstable when the controlling force
- AIncreases as the radius of rotation decreases
- BIncreases as the radius of rotation increases
- CDecreases as the radius of rotation increases
- DRemains constant for all radii of rotation
16.A spring controlled governor is said to be isochronous when the controlling force
- AIncreases as the radius of rotation decreases
- BIncreases as the radius of rotation increases
- CDecreases as the radius of rotation increases
- DRemain constant for all radii of rotation
17.In gramophones for adjusting the speed of the turntable, the following type of governor is commonly employed
- AHartung governor
- BWilson Hartnell governor
- CPickering governor
- DInertia governor
18.If the radius of gyration of a compound pendulum about an axis through e.g. is more, then its frequency of oscillation will be
- ALess
- BMore
- CSame
- DData are insufficient to determine same
19.The lower pair is a
- AOpen pair
- BClosed pair
- CSliding pair
- DPoint contact pair
20.When the primary direct crank of a reciprocating engine makes an angle of 'θ' with the line of stroke, then the secondary direct crank will make an angle of _________ with the line of stroke.
- Aθ/2
- Bθ
- C2θ
- D4θ