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Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 178 · 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.⚙️ An 8-tooth driver gear turns a 40-tooth driven gear. The driven gear turns 3 times. How many times did the driver turn?
  2. 2.⚙️ A 15-tooth gear drives a 45-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  3. 3.⚙️ A 45-tooth driver gear turns a 15-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  4. 4.🔢 Gear ratio = driven teeth ÷ … (a) driver teeth (b) motor volts (c) wheel size (d) number of gears
  5. 5.🔢 A gear ratio of 3 (driven ÷ driver) means the driven gear turns … (a) 3 times louder (b) 3 times slower (c) 3 times bigger (d) 3 times faster
  6. 6.⚙️ A 10-tooth driver gear turns a 40-tooth driven gear. The driver turns 40 times. How many times does the driven gear turn?
  7. 7.⚙️ A motor makes 240 turns a minute with a 12-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 motor makes 270 turns a minute with a 10-tooth gear on it. That gear drives a 30-tooth gear. How many turns a minute does the 30-tooth gear make?
  9. 9.⚙️ A 12-tooth gear drives a 48-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  10. 10.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) zero (b) big (slow and strong) (c) small (fast, weak) (d) never important
  11. 11.⚙️ An 8-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  12. 12.⚙️ A 10-tooth driver gear turns a 20-tooth driven gear. The driven gear turns 4 times. How many times did the driver turn?
  13. 13.⚙️ A 60-tooth driver gear turns a 15-tooth driven gear. The driver turns 5 times. How many times does the driven gear turn?
  14. 14.⚙️ A 12-tooth driver gear turns a 24-tooth driven gear. The driver turns 14 times. How many times does the driven gear turn?
  15. 15.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driver turns 16 times. How many times does the driven gear turn?
  16. 16.⚙️ An 8-tooth driver gear turns a 40-tooth driven gear. The driver turns 5 times. How many times does the driven gear turn?
  17. 17.⚙️ A motor makes 100 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?
  18. 18.⚙️ A 20-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  19. 19.⚙️ A 12-tooth driver gear turns a 60-tooth driven gear. The driver turns 45 times. How many times does the driven gear turn?
  20. 20.⚙️ A 20-tooth driver gear turns a 60-tooth driven gear. The driver turns 21 times. How many times does the driven gear turn?
  21. 21.⚙️ A motor makes 210 turns a minute with a 20-tooth gear on it. That gear drives a 60-tooth gear. How many turns a minute does the 60-tooth gear make?
  22. 22.⚙️ A 12-tooth driver gear turns a 48-tooth driven gear. The driver turns 40 times. How many times does the driven gear turn?
  23. 23.⚙️ A 20-tooth driver gear turns a 100-tooth driven gear. The driver turns 10 times. How many times does the driven gear turn?
  24. 24.⚙️ A 15-tooth driver gear turns a 30-tooth driven gear. The driver turns 18 times. How many times does the driven gear turn?
  25. 25.⚙️ A 15-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  26. 26.⚙️ An 8-tooth gear drives a 40-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  27. 27.⚙️ A 10-tooth driver gear turns a 30-tooth driven gear. The driven gear turns 4 times. How many times did the driver turn?
  28. 28.⚙️ A 15-tooth driver gear turns a 45-tooth driven gear. The driven gear turns 8 times. How many times did the driver turn?
  29. 29.⚙️ A 75-tooth driver gear turns a 15-tooth driven gear. The driver turns 3 times. How many times does the driven gear turn?
  30. 30.⚙️ A 30-tooth driver gear turns a 10-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  31. 31.⚙️ A 10-tooth driver gear turns a 30-tooth driven gear. The driver turns 21 times. How many times does the driven gear turn?
  32. 32.⚙️ A 10-tooth driver gear turns a 30-tooth driven gear. The driven gear turns 7 times. How many times did the driver turn?
  33. 33.⚙️ A motor makes 40 turns a minute with a 20-tooth gear on it. That gear drives a 40-tooth gear. How many turns a minute does the 40-tooth gear make?
  34. 34.⚙️ A 30-tooth driver gear turns a 15-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  35. 35.⚙️ A 12-tooth gear drives a 24-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  36. 36.⚙️ A motor makes 400 turns a minute with an 8-tooth gear on it. That gear drives a 40-tooth gear. How many turns a minute does the 40-tooth gear make?
  37. 37.⚙️ A 15-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  38. 38.⚙️ An 8-tooth driver gear turns a 40-tooth driven gear. The driver turns 20 times. How many times does the driven gear turn?
  39. 39.⚙️ A 40-tooth driver gear turns an 8-tooth driven gear. The driver turns 9 times. How many times does the driven gear turn?
  40. 40.⚙️ A 12-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?

Answer key

  1. 15
  2. 3
  3. 18
  4. driver teeth
  5. 3 times slower
  6. 10
  7. 120
  8. 90
  9. 4
  10. big (slow and strong)
  11. 16
  12. 8
  13. 20
  14. 7
  15. 8
  16. 1
  17. 20
  18. 60
  19. 9
  20. 7
  21. 70
  22. 10
  23. 2
  24. 9
  25. 30
  26. 5
  27. 12
  28. 24
  29. 15
  30. 18
  31. 7
  32. 21
  33. 20
  34. 8
  35. 2
  36. 80
  37. 75
  38. 4
  39. 45
  40. 36

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