Question

In a simple gear train, the velocity ratio depends on:

• A. Shaft distance
• B. Number of teeth on gears
• C. Module
• D. Pressure angle

Hint:

In gear trains, focus on the tooth count! The velocity ratio only depends on how many teeth each gear has.

Answer 1

The Correct Option is B

In a simple gear train, the velocity ratio (also known as gear ratio) is determined by the number of teeth on the driving and driven gears.
It is defined as:
\[ \text{Velocity Ratio} = \frac{\text{Number of teeth on driven gear}}{\text{Number of teeth on driver gear}} \]
This means that the actual sizes or distances between shafts do not directly affect the velocity ratio — only the tooth count does.
- Option (1): Shaft distance affects center distance but not the velocity ratio.
- Option (3): Module defines tooth size but doesn't affect the ratio if number of teeth are known.
- Option (4): Pressure angle affects the tooth profile but not the gear ratio.