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Why do bicycles have gears?
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Gears allow a cyclist to pedal at a steady rate, even when climbing hills. The gearshift lifts the chain from one cog wheel to another. Large cog wheels turn slowly, making it easier to cycle uphill. Small cog wheels turn quickly, making it easier to pedal downhill.
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Previous:
Back
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Book:
Best Ever Q&A
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Section:
Science & Technology
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Chapter:
Everyday Science
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