Engineering Questions with Answers - Multiple Choice Questions
Machine Kinematics MCQ – Law of Gearing – 2
1 - Question
A side and face cutter 125 mm diameter has 10 teeth. It operates at a cutting speed of 14 m/min with a table traverse 100 mm/min. The feed per tooth of the cutter is
a) 10 mm
b) 2.86 mm
c) 0.286 mm
d) 0.8 mm
View Answer
Answer: c
Explanation: пDN = 14,
N = 14000/3.14 x 125 = 35.65
Feed for tooth = table traverse/ N x no. of teeth = 100/35.65 x 10 = 0.286 mm.
2 - Question
Consider the following statements in case of reverted gear train:
1. The direction of rotation of the first and the last gear is the same.
2. the direction of rotation of the first and the last gear is opposite.
3. The first and the last gears are on the same shaft.
4. The first and the last gears are on separate but co-axial shafts.
Which of these statements is/are correct?
a) 1 and 3
b) 2 and 3
c) 2 and 4
d) 4 alone
View Answer
Answer: d
Explanation: Only fourth statement is correct.
3 - Question
The dynamic load on a gear is due to
1. inaccurancies of tooth spacing
2. irregularities in tooth profile
3. deflection of the teeth under load
4. type of service
Which of the above statements are correct?
a) 1,2 and 3
b) 2,3 and 4
c) 1,3 and 4
d) 1,2 and 4
View Answer
Answer: a
Explanation: The dynamic load on a gear is due to
1. inaccurancies of tooth spacing
2. irregularities in tooth profile
3. deflection of the teeth under load.
4 - Question
Consider the following statements:
A 200 stub tooth system is generally preferred in spur gears as it results in
1. stronger teeth
2. lesser number of teeth on the pinion
3. lesser chances of surface fatigue failure
4. reduction of interference
Which of the above statements are correct?
a) 1,2 and 4
b) 3 and 4
c) 1 and 3
d) 1,2,3 and 4
View Answer
Answer: a
Explanation: A 200 stub tooth system is generally preferred in spur gears as it results in
1. stronger teeth
2. lesser number of teeth on the pinion
3. reduction of interference.
5 - Question
An involute rack with 200 pressure angle meshes with a pinion of 14.50 pressure angle.
a) True
b) False
View Answer
Answer: b
Explanation: Such a matching is impossible.
6 - Question
When a pair of spur gears of the same material is in mesh, the design is based on pinion.
a) True
b) False
View Answer
Answer: a
Explanation: For a pair of gears of the same material in mesh, the strength factor of the pinion is less than that of the gear.
7 - Question
Consider the following modifications regarding avoiding the interference between gears:
1. The centre distance between meshing gears be increased
2. Addendum of the gear be modified
3. Teeth should be undercut slightly at the root
4. Pressure angle should be increased
5. Circular pitch be increased
Which of these are effective in avoiding interference?
a) 1,2 and 3
b) 2,3,4 and 5
c) 1,4 and 5
d) 3,4 and 5
View Answer
Answer: a
Explanation: None.
8 - Question
In a reverted gear train, two gears P and Q are meshing, Q-R is a compound gear, and R and S are meshing. The modules of P and R are 4 mm and 5 mm respectively. The numbers of teeth in P, Q and r are 20, 40 and 25 respectively. The number of teeth in S is
a) 23
b) 35
c) 50
d) 53
View Answer
Answer: a
Explanation: C = 1/2m1(zp + zq) = 1/2m2(zr + zs)
4(20 + 40) = 5(25 + zs)
zs = 23.
9 - Question
When two spur gears having involute profiles on their teeth engage, the line of action is tangential to the
a) pitch circles
b) dedendum circles
c) addendum circles
d) base circles
View Answer
Answer: a
Explanation: None.
10 - Question
If the annular wheel of an epicyclic gear train has 100 teeth and the planet wheel has 20 teeth, the number of teeth on sun wheel is
a) 80
b) 60
c) 40
d) 20
View Answer
Answer: b
Explanation: 2dp + ds = da
2zp + zs = za
2 x 20 + zs = 100
zs = 60.