1) Match the following Group 1 items with Group 2 items and select the correct option
1. Helical gears ------------------------------------------- A. Intersecting shafts
2. Bevel gears --------------------------------------------- B. Rotary motion into reciprocating motion
3. Spiral gears --------------------------------------------- C. Non-parallel nor intersecting
4. Rack and pinion --------------------------------------- D. Parallel shafts
a. 1 – A, 2 – C, 3 – D, 4 – B
b. 1 – D, 2 – A, 3 – C, 4 – B
c. 1 – B, 2 – D, 3 – C, 4 – A
d. 1 – C, 2 – A, 3 – B, 4 – D
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2) Which of the following statements is true for gear drive?
a. Gear drives can transmit very large power
b. Gear drives have low transmission efficiency
c. Gear drives require more space
d. All of the above
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3) Herring-bone gears are also known as
a. Hypoid gears
b. Helical gears
c. Spiral gears
d. None of the above
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4) What is meant by interference?
a. Mating of conjugate profiles of a tooth
b. Mating of involute profiles of a tooth
c. Mating of non-involute profiles of a tooth
d. All of the above
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5) If number of teeth on pinion and wheel are equal, then which relation is used to obtain minimum number of teeth in order to avoid interference with wheel
where Aw = addendum coefficient of wheel
a. 2 Aw / [ √(1+ 3 sin2 Φ) ] - 1
b. Aw / [ √(1+ 3 sin2 Φ) ] - 1
c. 2 Aw / [ √(1+ 2 sin2 Φ) ] - 1
d. Aw / [ √(1+ 2 sin2 Φ) ] - 1
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6) Which among the following relations is used to relate transverse pressure angle and normal pressure angle for helical gears?
where Φn = normal pressure angle & Φt = transverse pressure angle
a. cos α = tan Φn / tan Φt
b. cos α = tan Φn x tan Φt
c. cos α = tan Φt / tan Φn
d. None of the above
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7) Pitch circle diameter (de) of formative spur gear is given as
a. d / cos α
b. d / sin2 α
c. d / cot2 α
d. d / cos2 α
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8) Calculate center distance between two helical gears which has helix angle of 20o, when normal module is 10. Pinion and gear have 30 and 70 teeth respectively
a. 532.02 mm
b. 212.78 mm
c. 500 mm
d. None of the above
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9) Tangential force acting on the helical gear is 5000 N. Calculate the axial force acting on a helical gear having helix angle of 25o.
a. 2113.09 N
b. 4531.53 N
c. 2331.53 N
d. 10722.5 N
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10) Normal pressure angle and helix angle are 25o and 30o respectively. Tangential force acting on helical gear is 3500 N. Calculate radial force acting on the gear
a. 6.51 kN
b. 1.88 kN
c. 3.26 kN
d. None of the above
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11) In which type of gear trains, shaft axes which are mounted by gear wheels have relative motion between them?
a. Compounded gear train
b. Simple gear train
c. Epicyclic gear train
d. Reverted gear train
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12) In which type of vehicles, differential gear box is mounted on rear wheel axle?
a. Light duty vehicles
b. Heavy duty vehicles
c. both a and b
d. none of the above
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13) Which type of gear train and gears are used in Humpage Gear Box?
a. Epicyclic gear train with bevel gears
b. Epicyclic gear train with worm gears
c. Reverted gear train with bevel gears
d. Reverted gear train with worm gears
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14) What is meant by an idle gear?
a. Gears between driver and driven gears
b. Gears used when driver and driven gears move in same direction
c. Both a. and b.
d. None of the above
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15) In simple gear trains, velocity ratio is independent of idle gears
a. True
b. False
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16) Motion in stepped regulation method is obtained by
a. electrical systems
b. belt drive
c. hydraulic systems
d. All of the above
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17) Which formula is used to calculate extreme spindle speed (nmax) of a machine tool gearbox?
a. 1000 Vmax / pdmax
b. 1000 Vmax / pdmin
c. 60 Vmax / pdmin
d. 60 Vmax / pdmax
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18) Which gearboxes provide an arithmetic series of feed steps suitable for cutting threads?
a. Epicyclic gear box
b. Differential gear box
c. Norton gear box
d. None of the above
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19) Which of the following statements is true for stepless regulation of speed and feed rate?
1. Stepless regulation has noisy operation
2. Stepless regulation is compact
3. Less costly than stepped regulation system
4. Speed can only be adjusted only after stopping the machine
a. Statement 1, 2 and 3
b. Only statement 2
c. Only statement 4
d. All the statements are true
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20) What is the difference between cone variators and face plate variators?
a. Velocity distribution over contact area for cone variators is better than face plate variators
b. Velocity distribution over contact area for face plate variators is better than cone variators
c. Cone and face plate variators have different speed variation range
d. None of the above
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Answer
Explanation
Related Ques
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ANSWER: Velocity distribution over contact area for cone variators is better than face plate variators
Explanation:
No explanation is available for this question!
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21) Degree of freedom for gyroscope rotor is
a. 1
b. 2
c. 3
d. 5
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22) How is the direction of precession vector decided by right hand rule?
a. Thumb denotes direction of precession vector
b. Curled fingers denote direction of precession vector
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23) Which of the following statements is/are false for active gyroscopic couple?
a. Reactive gyroscopic couple and active gyroscopic couple are opposite in direction
b. In right hand rule, curled fingers denote direction of precession
c. In active gyroscopic couple spin vector and precession vector are parallel to each other
d. All the statements are false
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Answer
Explanation
Related Ques
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ANSWER: In active gyroscopic couple spin vector and precession vector are parallel to each other
Explanation:
No explanation is available for this question!
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24) What is the gyroscopic couple acting on the disc which has mass moment of inertia equal to 0.02135 kg-m2. If disc has a speed of 500 rpm and is made to precess at 100 rpm.
a. 13.21 N-m
b. 11.70 N-m
c. 10.23 N-m
d. Incomplete data
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25) Calculate gyroscopic couple acting on a disc which has radius of 135 mm. Angular and precessional velocities are 15 rad/sec and 7 rad/sec respectively.
Assume density = 7810 kg/m3 and thickness of disc = 30 mm
a. 12.83 N-m
b. 10.99 N-m
c. 11 N-m
d. Incomplete data
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