Gears
Use gear ratios and tooth counts to find the last gear’s speed and rotation direction.
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Example
Example
Example · Standard
B and C share a shaft.
| Gear | Teeth | Speed · Direction |
|---|---|---|
| A | 18 | 120 RPM · Clockwise |
| B | 12 | To find |
| C | 18 | To find |
| D | 12 | To find |
3–4 gears · idlers and one shared shaft
Your last settings are ready. Change them whenever you like.
6 questions · No time limit
- Questions answered
- 0 / 6
- Active time
- 0:00
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Start with gear A. Follow each contact and choose the last gear’s speed and direction.
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Reload pageExplore the method
Use gear ratios, shared shafts and direction changes to solve simple and compound gear trains.
On by default unless you turn it off. Saved choices are kept. Shares starts, completions, replays and error categories. For ChatGPT visits, starts and completions may include the first QuickenBrain page and country. No answers, drawings or names.
How this data is usedHelp
All gears are viewed from the same side. Meshing teeth reverse direction: next speed = current speed × current tooth count ÷ next tooth count. Gears fixed to the same shaft keep the same speed and direction. Visible axles join the centers of gears on a shared shaft. RPM means revolutions per minute.
Each round has six questions and no time limit. Choosing an answer locks it. Review the steps, then move to the next question. Finish all six to save the round. Active time includes reviewing the steps, but does not count time when this page is hidden. Speed does not affect your score.
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Original practice puzzles, not a standardized assessment.
About this practice
Learn a method
Follow a gear trainUse gear ratios and tooth counts to find the last gear’s speed and rotation direction.
Report a problem
On by default unless you turn it off. Saved choices are kept. Shares starts, completions, replays and error categories. For ChatGPT visits, starts and completions may include the first QuickenBrain page and country. No answers, drawings or names.
How this data is used