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Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 270 · 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 motor makes 160 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?
  2. 2.⚙️ A 20-tooth driver gear turns a 100-tooth driven gear. The driver turns 10 times. How many times does the driven gear turn?
  3. 3.🔢 A gear ratio of 3 (driven ÷ driver) means the driven gear turns … (a) 3 times louder (b) 3 times faster (c) 3 times slower (d) 3 times bigger
  4. 4.⚙️ A 15-tooth gear drives a 60-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  5. 5.⚙️ A 40-tooth driver gear turns a 10-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  6. 6.⚙️ A 50-tooth driver gear turns a 10-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  7. 7.⚙️ A 36-tooth driver gear turns a 12-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  8. 8.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) small (fast, weak) (b) never important (c) zero (d) big (slow and strong)
  9. 9.⚙️ A motor makes 120 turns a minute with an 8-tooth gear on it. That gear drives a 32-tooth gear. How many turns a minute does the 32-tooth gear make?
  10. 10.⚙️ An 8-tooth driver gear turns a 40-tooth driven gear. The driver turns 10 times. How many times does the driven gear turn?
  11. 11.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  12. 12.⚙️ A motor makes 160 turns a minute with a 15-tooth gear on it. That gear drives a 30-tooth gear. How many turns a minute does the 30-tooth gear make?
  13. 13.⚙️ A 16-tooth driver gear turns an 8-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  14. 14.⚙️ A motor makes 140 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?
  15. 15.⚙️ A 12-tooth driver gear turns a 24-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  16. 16.⚙️ A 12-tooth driver gear turns a 60-tooth driven gear. The driver turns 25 times. How many times does the driven gear turn?
  17. 17.⚙️ A motor makes 240 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.🔢 Gear ratio = driven teeth ÷ … (a) number of gears (b) driver teeth (c) motor volts (d) wheel size
  19. 19.⚙️ A 20-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  20. 20.⚙️ A 10-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  21. 21.⚙️ A 20-tooth driver gear turns a 40-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  22. 22.⚙️ A 45-tooth driver gear turns a 15-tooth driven gear. The driver turns 3 times. How many times does the driven gear turn?
  23. 23.⚙️ A 20-tooth driver gear turns a 60-tooth driven gear. The driver turns 27 times. How many times does the driven gear turn?
  24. 24.⚙️ A 12-tooth driver gear turns a 60-tooth driven gear. The driver turns 45 times. How many times does the driven gear turn?
  25. 25.⚙️ A 30-tooth driver gear turns a 10-tooth driven gear. The driver turns 3 times. How many times does the driven gear turn?
  26. 26.⚙️ A 10-tooth driver gear turns a 50-tooth driven gear. The driver turns 50 times. How many times does the driven gear turn?
  27. 27.⚙️ A 20-tooth driver gear turns a 100-tooth driven gear. The driver turns 50 times. How many times does the driven gear turn?
  28. 28.⚙️ A motor makes 360 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?
  29. 29.⚙️ An 8-tooth gear drives a 32-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  30. 30.⚙️ A 12-tooth gear drives a 36-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  31. 31.⚙️ A 15-tooth driver gear turns a 60-tooth driven gear. The driven gear turns 9 times. How many times did the driver turn?
  32. 32.⚙️ A 12-tooth driver gear turns a 36-tooth driven gear. The driver turns 9 times. How many times does the driven gear turn?
  33. 33.⚙️ An 8-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  34. 34.⚙️ A 15-tooth gear drives a 30-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  35. 35.⚙️ A 15-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  36. 36.⚙️ A 12-tooth driver gear turns a 60-tooth driven gear. The driven gear turns 5 times. How many times did the driver turn?
  37. 37.⚙️ A motor makes 480 turns a minute with a 10-tooth gear on it. That gear drives a 40-tooth gear. How many turns a minute does the 40-tooth gear make?
  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 15-tooth driver gear turns a 75-tooth driven gear. The driven gear turns 10 times. How many times did the driver turn?
  40. 40.⚙️ A 75-tooth driver gear turns a 15-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?

Answer key

  1. 80
  2. 2
  3. 3 times slower
  4. 4
  5. 24
  6. 20
  7. 24
  8. big (slow and strong)
  9. 30
  10. 2
  11. 3
  12. 80
  13. 12
  14. 70
  15. 4
  16. 5
  17. 60
  18. driver teeth
  19. 80
  20. 40
  21. 2
  22. 9
  23. 9
  24. 9
  25. 9
  26. 10
  27. 10
  28. 120
  29. 4
  30. 3
  31. 36
  32. 3
  33. 40
  34. 2
  35. 75
  36. 25
  37. 120
  38. 4
  39. 50
  40. 20

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