======Bicycle Gears======


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**Alternative titles:** Gears and Mechanical Advantage
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====Summary====                   
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====Procedure====  
  - Show a bicycle and point out the pedals, chain, and gears.  
  - Explain that the pedals act as levers, applying effort force to turn the gear (a wheel and axle).  
  - Demonstrate how the chain transfers motion from the front gear to the back wheel gear.  
  - Shift to a low gear and pedal—students should notice it is easier to pedal but the bike moves more slowly.  
  - Shift to a high gear and pedal—students should notice it takes more effort but the bike moves farther per pedal turn.  
  - Draw a simple diagram showing large vs. small gears connected by a chain.



====Links==== 
Explaining the Gear System on a Bicycle - Virtual Elementary School: 
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====Variations====
  * Use a stationary bike with visible gears for indoor demonstration.  
  * Show videos of cyclists using different gears on hills and flat terrain.  
  * Compare gear ratios by counting the teeth on large vs. small gears.



====Safety Precautions====
  * If using a real bike, ensure it is stable (e.g., on a stand) before pedaling.  
  * Keep fingers and clothing away from moving chains and gears.  
  * Demonstrate outdoors if riding the bicycle, with helmets required.




====Questions to Consider====
  * Why is it easier to pedal uphill in a low gear? (Because the gear ratio increases mechanical advantage, requiring less force per pedal turn.)  
  * Why does a high gear make the bike go faster on flat ground? (Because one pedal turn moves the wheel farther, trading force for speed.)  
  * How do gears show the trade-off between force and distance? (Smaller force over more turns vs. larger force over fewer turns.)