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Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 111 · 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 15-tooth gear drives a 45-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  2. 2.🔢 A gear ratio of 3 (driven ÷ driver) means the driven gear turns … (a) 3 times bigger (b) 3 times slower (c) 3 times louder (d) 3 times faster
  3. 3.🔢 Gear ratio = driven teeth ÷ … (a) driver teeth (b) motor volts (c) wheel size (d) number of gears
  4. 4.⚙️ An 8-tooth gear drives a 24-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  5. 5.⚙️ A 15-tooth driver gear turns a 30-tooth driven gear. The driven gear turns 4 times. How many times did the driver turn?
  6. 6.⚙️ A 15-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  7. 7.⚙️ A motor makes 20 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 15-tooth gear drives a 30-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  9. 9.⚙️ A motor makes 220 turns a minute with a 10-tooth gear on it. That gear drives a 20-tooth gear. How many turns a minute does the 20-tooth gear make?
  10. 10.⚙️ A 100-tooth driver gear turns a 20-tooth driven gear. The driver turns 5 times. How many times does the driven gear turn?
  11. 11.⚙️ A 12-tooth driver gear turns a 60-tooth driven gear. The driven gear turns 5 times. How many times did the driver turn?
  12. 12.⚙️ A 30-tooth driver gear turns a 15-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  13. 13.⚙️ A 10-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  14. 14.⚙️ An 8-tooth driver gear turns a 24-tooth driven gear. The driver turns 15 times. How many times does the driven gear turn?
  15. 15.⚙️ A motor makes 60 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?
  16. 16.⚙️ A motor makes 360 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?
  17. 17.⚙️ A 12-tooth driver gear turns a 60-tooth driven gear. The driver turns 45 times. How many times does the driven gear turn?
  18. 18.⚙️ 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?
  19. 19.⚙️ A motor makes 330 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?
  20. 20.⚙️ A 60-tooth driver gear turns a 20-tooth driven gear. The driver turns 1 time. How many times does the driven gear turn?
  21. 21.⚙️ A 20-tooth driver gear turns an 80-tooth driven gear. The driver turns 40 times. How many times does the driven gear turn?
  22. 22.⚙️ A 10-tooth gear drives a 50-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  23. 23.⚙️ A 10-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  24. 24.⚙️ A 15-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  25. 25.⚙️ A motor makes 150 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 60-tooth driver gear turns a 15-tooth driven gear. The driver turns 3 times. How many times does the driven gear turn?
  27. 27.⚙️ A 10-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  28. 28.⚙️ A 12-tooth gear drives a 36-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  29. 29.⚙️ A 75-tooth driver gear turns a 15-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  30. 30.⚙️ A 12-tooth driver gear turns a 24-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  31. 31.⚙️ A 40-tooth driver gear turns an 8-tooth driven gear. The driver turns 1 time. How many times does the driven gear turn?
  32. 32.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) small (fast, weak) (b) zero (c) never important (d) big (slow and strong)
  33. 33.⚙️ A 20-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  34. 34.⚙️ A motor makes 240 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?
  35. 35.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  36. 36.⚙️ A 12-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  37. 37.⚙️ A 10-tooth driver gear turns a 50-tooth driven gear. The driver turns 25 times. How many times does the driven gear turn?
  38. 38.⚙️ A 48-tooth driver gear turns a 12-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  39. 39.⚙️ A 12-tooth driver gear turns a 60-tooth driven gear. The driven gear turns 3 times. How many times did the driver turn?
  40. 40.⚙️ A motor makes 60 turns a minute with a 12-tooth gear on it. That gear drives a 36-tooth gear. How many turns a minute does the 36-tooth gear make?

Answer key

  1. 3
  2. 3 times slower
  3. driver teeth
  4. 3
  5. 8
  6. 60
  7. 10
  8. 2
  9. 110
  10. 25
  11. 25
  12. 16
  13. 50
  14. 5
  15. 20
  16. 120
  17. 9
  18. 70
  19. 110
  20. 3
  21. 10
  22. 5
  23. 40
  24. 45
  25. 30
  26. 12
  27. 20
  28. 3
  29. 20
  30. 3
  31. 5
  32. big (slow and strong)
  33. 80
  34. 80
  35. 4
  36. 36
  37. 5
  38. 24
  39. 15
  40. 20

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