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1) Degree of freedom for gyroscope rotor is a. 1 b. 2 c. 3 d. 5
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2) 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 c. Both A & B d. None of these
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3) 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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4) According to synthesis of mechanism, which synthesis step includes degree of freedom for a specified motion? a. Type synthesis b. Number synthesis c. Dimensional synthesis d. All of the above
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5) Branch defect is observed in a. grashof type four bar chain linkage b. non-grashof type four bar chain linkage c. both grashof and non-grashof type four bar chain linkage d. none of the above
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6) Which of the following statements is/are true for errors in function generation? a. At precision points structural error is zero b. Structural errors exist only if mechanical errors exist in synthesized mechanism c. Structural errors cannot be reduced by increasing number of precession points d. All of the above
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7) Why is an overlay method used in synthesis of a function generation? a. It is used to generate precision positions in four bar mechanism b. It is used to generate precision positions in slider crank mechanism c. both a and b d. none of the above
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8) Which type of cam does not require any external force to have contact between cam and follower? a. Preloaded spring cam b. Conjugate cam c. Both a. and b. d. None of the above
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9) Which of the following statements is/are true for cam profile? a. Pitch point on the pitch curve has minimum pressure angle b. In case of roller follower, trace point represents centre of the roller c. Pitch circle is drawn through trace point from the center of cam d. All of the above
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10) A cam operating roller follower has the following dimensions, radius of base and nose circle as 15 mm and 10 mm respectively and distance between them is 8 mm. Determine lift made by the follower a. 5 mm b. 12.5 mm c. 3 mm d. 17 mm
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11) What is meant by jump phenomenon in cam and follower system? a. Follower looses contact with cam surface when cam rotates beyond particular speed due to inertia forces b. Follower looses contact with cam surface when follower rotates beyond particular speed due to gravitational force c. Follower looses contact with cam surface when cam rotates beyond particular speed due to gravitational forces d. None of the above
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12) Interference in gear tooth profiles can be avoided by a. modifying tooth profile b. modifying center distance between pinion and wheel c. both a. and b. d. none of the above
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13) In involute gears what is the effect of center distance variation on velocity ratio? a. Velocity ratio increases b. Velocity ratio decreases c. It has no effect on velocity ratio d. None of the above
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14) Calculate number of teeth on wheel to avoid interference, if wheel has addendum coefficient of one and velocity ratio 4. Pressure angle being 22° and gear ratio of 2 a. 10 b. 24 c. 34 d. None of the above
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15) What is meant by contact ratio in gears? a. Ratio of length of arc of approach and circular pitch b. Ratio of circular pitch and length of arc of contact c. Ratio of length of arc of recess and circular pitch d. Ratio of length of arc of contact and circular pitch
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16) Calculate the number of teeth on wheel, when number of teeth on pinion and wheel are equal. Pressure angle is 25° a. 11 b. 12 c. 7 d. 9
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17) Which of the following conditions specify maximum efficiency of spiral gears? a. (θ + α) / 2 b. (θ – α) / 2 c. Both a. and b. d. None of the above
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18) Back cone angle is observed in which type of gears? a. Spur gears b. Helical gears c. Bevel gears d. None of the above
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19) Which formula is used to calculate maximum efficiency of worm gear? a. tan δ / tan ( δ + Φ) b. (1 – sin Φ) / ( 1 + sin Φ) c. tan ( δ + Φ) / tan δ d. (1 + sin Φ) / ( 1 – sin Φ)
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20) If friction angle Φ = 5.43°, calculate maximum efficiency of worm gearing a. 82.71 % b. 90.53 % c. 80.23 % d. None of the above
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