250+ TOP MCQs on Mechanical Actuating Systems – Gear and Gear Trains – 1 and Answers

Mechatronics Multiple Choice Questions on “Mechanical Actuating Systems – Gear and Gear Trains – 1”.

1. What is the module of a gear if its pitch diameter is 10mm and it contains 5 teeth?
a) 2
b) 3
c) 4
d) 5
Answer: a
Clarification: Given:
Pitch diameter = 10mm
No. Of teeth=5 teeth
Module=Pitch diameter/No. Of teeth
Module=>10/5 =2.

2. What is the pitch of a gear if the gear contains 30 teeth and diameter of the gear is 6 inches?
a) 2
b) 3
c) 4
d) 5
Answer: d
Clarification: Given:
No. Of teeth=30 teeth
Diameter=6 inches
Pitch=Number of teeth/Diameter
Pitch=30/6=5.

3. What is the torque offered by a gear, if the tangential force is 20 N and radius of the gear is 1m?
a) 5Nm
b) 15Nm
c) 20Nm
d) 2.55Nm
Answer: c
Clarification: Given:
Tangential force=20N
Radius of the gear=1m
Torque=tangential force (F)*Radius(R)
Torque=20*1=>20Nm.

4. What is the radius of a gear, if torque generated by the gear is 20Nm and the tangential force is 5N?
a) 5m
b) 15m
c) 10m
d) 4m
Answer: d
Clarification: Given:
No. Of teeth=30 teeth
Diameter=6 inches
Pitch=Number of teeth/Diameter
Pitch=30/6 = 5.

5. The pitch of a gear is defined as the number of teeth per unit pitch circle radius.
a) True
b) False
Answer: b
Clarification: The pitch of a gear is not the number of teeth per unit pitch circle radius. It is defined as the number of teeth per unit pitch circle diameter. The diameter is taken in inches.

6. The radial distance between root circle and pitch circle is called addendum.
a) True
b) False
Answer: b
Clarification: The radial distance between root circle and pitch circle is not called addendum. The radial distance between root circle and pitch circle is called dedendum. Radial distance between addendum circle and pitch circle is called addendum.

7. What is the velocity ratio of two gears if the driver gear has 15 teeth and driven gear has 5 teeth?
a) 2:1
b) 3:1
c) 4:3
d) 5:1
Answer: b
Clarification: Given:
No. Of teeth of driver gear=15
No. Of teeth of driven gear=5
Velocity ratio=No. of teeth of driver gear/No. of teeth of driven gear
Velocity ratio => 15/5=3:1.

8. What is the torque offered by a gear, if the tangential force is 10N and radius of the gear is 0.5m?
a) 5Nm
b) 15Nm
c) 10Nm
d) 2.55Nm
Answer: a
Clarification: Given:
Tangential force=10N
Radius of the gear=0.5m
Torque=tangential force (F)*Radius(R)
Torque=10*0.5 => 5Nm.

9. What is the radius of a gear, if torque generated by the gear is 20Nm and the tangential force is 5N?
a) 5m
b) 4m
c) 10m
d) 2m
Answer: b
Clarification: 4m is the radius of a gear, if torque generated by the gear is 20Nm and the tangential force is 5N. Since the formula for torque(T) is tangential force (F)*Radius(R), so radius=Torque(T)/Tangential force(F) which gives radius = 20Nm/5m => 4m.

10. What is the module of a gear if its pitch diameter is 15mm and it contains 3 teeth?
a) 2
b) 3
c) 4
d) 5
Answer: d
Clarification: Given:
Pitch diameter = 15mm
No. Of teeth=3 teeth
Module=Pitch diameter/No. Of teeth
Module=>15/3=5.

11. What is the velocity ratio of two gears if the driver gear has 20 teeth and driven gear has 10 teeth?
a) 2:1
b) 3:2
c) 4:3
d) 5:1
Answer: a
Clarification: Given:
No. Of teeth of driver gear=20
No. Of teeth of driven gear=10
Velocity ratio=No. of teeth of driver gear/No. of teeth of driven gear
Velocity ratio => 20/10=2:1.

12. What is the speed ratio of two gears if the speed of the driver gear has 20 km/hr and driven gear has 10km/hr?
a) 2:1
b) 3:2
c) 4:3
d) 5:1
Answer: a
Clarification: Given:
Speed of the driver gear=20km/hr
Speed of the driven gear = 10km/hr
Speed ratio=speed of the driver gear/speed of the driven gear
Speed ratio=>20/10=2:1.

13. What is the speed ratio of two gears if the speed of the driver gear has 25 km/hr and driven gear has 10km/hr?
a) 2:1
b) 3:2
c) 4:3
d) 5:2
Answer: d
Clarification: Given:
Speed of the driver gear=25km/hr
Speed of the driven gear = 10km/hr
Speed ratio=speed of the driver gear/speed of the driven gear
Speed ratio=>25/10=5:2.

14. What is the train value of a gear train if the velocity ratio is 2:5?
a) 2:1
b) 3:2
c) 4:3
d) 5:2
Answer: d
Clarification:
Given: velocity ratio=2:5
Train value=1/(velocity ratio)
Train value=1/(2:5)=5:2.

15. What is the train value of a gear train if the velocity ratio is 2:1?
a) 2:1
b) 1:2
c) 4:3
d) 5:2
Answer: b
Clarification:
Given: velocity ratio=2:1
Train value=1/(velocity ratio)
Train value=1/(2:1)=1:2.