# MCQs on Mechanical Actuating Systems – Gear and Gear Trains – 2

1 - Question

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

2 - Question

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

3 - Question

What is the velocity ratio of two gears if the driver gear has angular velocity of 20m/s and driven gear has angular velocity of 10m/s?
a) 2:1
b) 3:2
c) 4:3
d) 5:1
Explanation: Given: Angular velocity of the driver gear=20km/hr Angular velocity of the driven gear = 10km/hr Velocity ratio= speed of the driver gear/ speed of the driven gear Velocity ratio=>20/10=2:1. advertisement

4 - Question

What is the angular velocity of driven gear if the driver gear has angular velocity of 30m/s and velocity ratio of two gears is 3:2?
a) 10m/s
b) 20m/s
c) 30m/s
d) 40m/s
Explanation: Given: Angular velocity of the driver gear=30 km/hr Velocity ratio= speed of the driver gear/speed of the driven gear 3/2=30/Angular velocity of the driven gear Angular velocity of the driven gear=20m/s.

5 - Question

Which gear cannot connect two parallel shafts?
a) Spur gear
b) Helical gear
c) Bevel gear
d) Double helical gear
Explanation: Bevel gear cannot connect two parallel shafts. It is used to transmit torque or power between shafts that are not parallel to each other. Generally it is used to transmit power between perpendicular shafts.

6 - Question

Spur gears can transmit power between perpendicular shafts.
a) True
b) False
Explanation: Spur gears cannot transmit power between perpendicular shafts. These are simplest type of gear. It can transmit power between parallel shafts. Bevel gears are used to transmit power between perpendicular shafts.

7 - Question

Which gear can be used to transmit rectilinear motion?
a) Spur gear
b) Helical gear
c) Bevel gear
d) Rack and pinion gear
Explanation: Rack and pinion gear can be used to transmit rectilinear motion. This setup contains a straight rack and a circular spur gear. When the spur gear moves, it drives the rack in rectilinear fashion.

8 - Question

Which gear train is also called as “Sun and planet gear train”?
a) Simple gear train
b) Reverted gear train
c) Compound gear train
d) Epicyclic gear train
Explanation: Epicyclic gear train is also called as “Sun and planet gear train”. It is called so because the driven gear revolves around the driver gear when the gear moves. The driver and the driven gear are connected to each other.

9 - Question

Which gear train contains more than one gear in a single shaft?
a) Simple gear train
b) Helical gear train
c) Compound gear train
d) Epicyclic gear train
Explanation: Compound gear train contains more than one gear in a single shaft. The size of the gears may or may not be same, but a single shaft must contain more than one gear to be called as compound gear train.

10 - Question

In reverted gear train, the input and output gears should be co-axial.
a) True
b) False
Explanation: In reverted gear train, the input and output gears should be co-axial. Reverted gear train is a type of compound gear train, where the shaft of the driver gear and driven gear must be parallel to each other.

11 - Question

Which gear train contains only one gear in a single shaft and the driven gear does not revolve driven gear around it?
a) Simple gear train
b) Reverted gear train
c) Compound gear train
d) Epicyclic gear train
Explanation: Simple gear train contains only one gear in a single shaft and the driven gear does not revolve driven gear around it. It is the mist simple and most commonly used gear train. The shafts of driver and driven gear are also parallel to each other.

12 - Question

What is the velocity ratio of a gear train if the train value is 2:7?
a) 2:1
b) 2: 7
c) 7:2
d) 5:1
Explanation: Given: Train value velocity ratio=2:7 Velocity ratio=1/( Train value) Train value=1/(2:7)=7:2.

13 - Question

What is the velocity ratio of two gears if the driver gear has angular velocity of 15m/s and driven gear has angular velocity of 10m/s?
a) 2:1
b) 3:2
c) 4:3
d) 5:1
Explanation: Given: Angular velocity of the driver gear=15km/hr Angular velocity of the driven gear = 10km/hr Velocity ratio=speed of the driver gear/speed of the driven gear Velocity ratio=>15/10=3:2.

14 - Question

Reverted gear train is also called as planetary gear train.
a) True
b) False