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Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 164 · 40 questions
TalentJR

Robot tip (Teeth × turns): Teeth passing = driver teeth × driver turns. Driven turns = teeth passing ÷ driven teeth. Gear ratio = driven teeth ÷ driver teeth (a ratio of 3 means 3 times slower).

NameDateTime takenScore ___ / 40
  1. 1.⚙️ A 20-tooth gear drives a 100-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  2. 2.⚙️ A 15-tooth driver gear turns a 75-tooth driven gear. The driver turns 25 times. How many times does the driven gear turn?
  3. 3.⚙️ A 12-tooth driver gear turns a 24-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  4. 4.⚙️ A 15-tooth driver gear turns a 30-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  5. 5.⚙️ A 10-tooth driver gear turns a 30-tooth driven gear. The driver turns 12 times. How many times does the driven gear turn?
  6. 6.⚙️ A 20-tooth driver gear turns an 80-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  7. 7.⚙️ A motor makes 120 turns a minute with an 8-tooth gear on it. That gear drives a 24-tooth gear. How many turns a minute does the 24-tooth gear make?
  8. 8.⚙️ A 10-tooth driver gear turns a 20-tooth driven gear. The driven gear turns 10 times. How many times did the driver turn?
  9. 9.🔢 Gear ratio = driven teeth ÷ … (a) motor volts (b) number of gears (c) driver teeth (d) wheel size
  10. 10.⚙️ A 60-tooth driver gear turns a 15-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  11. 11.⚙️ An 8-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  12. 12.⚙️ An 8-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  13. 13.🔢 A gear ratio of 3 (driven ÷ driver) means the driven gear turns … (a) 3 times bigger (b) 3 times slower (c) 3 times faster (d) 3 times louder
  14. 14.⚙️ A 15-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  15. 15.⚙️ A motor makes 400 turns a minute with a 20-tooth gear on it. That gear drives a 100-tooth gear. How many turns a minute does the 100-tooth gear make?
  16. 16.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) never important (b) small (fast, weak) (c) zero (d) big (slow and strong)
  17. 17.⚙️ A motor makes 80 turns a minute with a 20-tooth gear on it. That gear drives an 80-tooth gear. How many turns a minute does the 80-tooth gear make?
  18. 18.⚙️ A 20-tooth driver gear turns a 10-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  19. 19.⚙️ A 30-tooth driver gear turns a 15-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  20. 20.⚙️ An 8-tooth driver gear turns a 40-tooth driven gear. The driver turns 30 times. How many times does the driven gear turn?
  21. 21.⚙️ A 100-tooth driver gear turns a 20-tooth driven gear. The driver turns 7 times. How many times does the driven gear turn?
  22. 22.⚙️ A 15-tooth driver gear turns a 45-tooth driven gear. The driven gear turns 3 times. How many times did the driver turn?
  23. 23.⚙️ A 15-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  24. 24.⚙️ A motor makes 330 turns a minute with a 15-tooth gear on it. That gear drives a 45-tooth gear. How many turns a minute does the 45-tooth gear make?
  25. 25.⚙️ A motor makes 200 turns a minute with a 12-tooth gear on it. That gear drives a 60-tooth gear. How many turns a minute does the 60-tooth gear make?
  26. 26.⚙️ A 10-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  27. 27.⚙️ A motor makes 550 turns a minute with a 10-tooth gear on it. That gear drives a 50-tooth gear. How many turns a minute does the 50-tooth gear make?
  28. 28.⚙️ A 10-tooth driver gear turns a 20-tooth driven gear. The driven gear turns 3 times. How many times did the driver turn?
  29. 29.⚙️ A 50-tooth driver gear turns a 10-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  30. 30.⚙️ A 10-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  31. 31.⚙️ A 10-tooth gear drives a 30-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  32. 32.⚙️ A 10-tooth gear drives a 20-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  33. 33.⚙️ A 15-tooth driver gear turns a 45-tooth driven gear. The driven gear turns 6 times. How many times did the driver turn?
  34. 34.⚙️ A 15-tooth driver gear turns a 45-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  35. 35.⚙️ A 20-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  36. 36.⚙️ A 20-tooth driver gear turns a 40-tooth driven gear. The driver turns 10 times. How many times does the driven gear turn?
  37. 37.⚙️ A 100-tooth driver gear turns a 20-tooth driven gear. The driver turns 1 time. How many times does the driven gear turn?
  38. 38.⚙️ A 12-tooth gear drives a 48-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  39. 39.⚙️ A 15-tooth gear drives a 45-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  40. 40.⚙️ A 20-tooth driver gear turns an 80-tooth driven gear. The driven gear turns 5 times. How many times did the driver turn?

Answer key

  1. 5
  2. 5
  3. 2
  4. 2
  5. 4
  6. 2
  7. 40
  8. 20
  9. driver teeth
  10. 32
  11. 32
  12. 16
  13. 3 times slower
  14. 75
  15. 80
  16. big (slow and strong)
  17. 20
  18. 16
  19. 8
  20. 6
  21. 35
  22. 9
  23. 30
  24. 110
  25. 40
  26. 40
  27. 110
  28. 6
  29. 40
  30. 20
  31. 3
  32. 2
  33. 18
  34. 2
  35. 40
  36. 5
  37. 5
  38. 4
  39. 3
  40. 20

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