Spur Gear - Mechanical Engineering (MCQ) questions and answers

1)   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
Answer  Explanation 

ANSWER: Ratio of length of arc of contact and circular pitch

Explanation:
No explanation is available for this question!


2)   Calculate the number of teeth on wheel, when number of teeth on pinion and wheel are equal. Pressure angle is 25o

a. 11
b. 12
c. 7
d. 9
Answer  Explanation 

ANSWER: 9

Explanation:
No explanation is available for this question!


3)   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
Answer  Explanation 

ANSWER: 2 Aw / [ √(1+ 3 sin2 Φ) ] - 1

Explanation:
No explanation is available for this question!


4)   Calculate number of teeth on wheel to avoid interference, if wheel has addendum coefficient of one and velocity ratio 4. Pressure angle being 22o and gear ratio of 2

a. 10
b. 24
c. 34
d. None of the above
Answer  Explanation 

ANSWER: 24

Explanation:
No explanation is available for this question!


5)   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
Answer  Explanation 

ANSWER: It has no effect on velocity ratio

Explanation:
No explanation is available for this question!


6)   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
Answer  Explanation 

ANSWER: both a. and b.

Explanation:
No explanation is available for this question!


7)   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
Answer  Explanation 

ANSWER: Mating of non-involute profiles of a tooth

Explanation:
No explanation is available for this question!


8)   Herring-bone gears are also known as

a. Hypoid gears
b. Helical gears
c. Spiral gears
d. None of the above
Answer  Explanation 

ANSWER: Helical gears

Explanation:
No explanation is available for this question!


9)   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
Answer  Explanation 

ANSWER: Gear drives can transmit very large power

Explanation:
No explanation is available for this question!


10)   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
Answer  Explanation 

ANSWER: 1 – D, 2 – A, 3 – C, 4 – B

Explanation:
No explanation is available for this question!