← Gear ratio sums lesson New set →

Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 144 · 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 80 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 gear ratio of 3 (driven ÷ driver) means the driven gear turns … (a) 3 times faster (b) 3 times slower (c) 3 times louder (d) 3 times bigger
  3. 3.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) never important (b) zero (c) small (fast, weak) (d) big (slow and strong)
  4. 4.⚙️ A 12-tooth gear drives a 60-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  5. 5.⚙️ A motor makes 300 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?
  6. 6.⚙️ A motor makes 80 turns a minute with an 8-tooth gear on it. That gear drives a 16-tooth gear. How many turns a minute does the 16-tooth gear make?
  7. 7.⚙️ A 12-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  8. 8.⚙️ A 10-tooth gear drives a 30-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  9. 9.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  10. 10.⚙️ A motor makes 180 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?
  11. 11.⚙️ A 10-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  12. 12.⚙️ A 10-tooth driver gear turns a 30-tooth driven gear. The driver turns 30 times. How many times does the driven gear turn?
  13. 13.⚙️ A 10-tooth driver gear turns a 20-tooth driven gear. The driven gear turns 9 times. How many times did the driver turn?
  14. 14.⚙️ A 40-tooth driver gear turns an 8-tooth driven gear. The driver turns 1 time. How many times does the driven gear turn?
  15. 15.⚙️ A 36-tooth driver gear turns a 12-tooth driven gear. The driver turns 5 times. How many times does the driven gear turn?
  16. 16.🔢 Gear ratio = driven teeth ÷ … (a) number of gears (b) wheel size (c) driver teeth (d) motor volts
  17. 17.⚙️ A 20-tooth driver gear turns a 10-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  18. 18.⚙️ An 8-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  19. 19.⚙️ A 24-tooth driver gear turns a 12-tooth driven gear. The driver turns 2 times. How many times does the driven gear turn?
  20. 20.⚙️ An 8-tooth driver gear turns a 24-tooth driven gear. The driven gear turns 9 times. How many times did the driver turn?
  21. 21.⚙️ A 10-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  22. 22.⚙️ A 48-tooth driver gear turns a 12-tooth driven gear. The driver turns 3 times. How many times does the driven gear turn?
  23. 23.⚙️ A 15-tooth gear drives a 30-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  24. 24.⚙️ A 15-tooth gear drives a 75-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  25. 25.⚙️ A 50-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 16-tooth driver gear turns an 8-tooth driven gear. The driver turns 7 times. How many times does the driven gear turn?
  27. 27.⚙️ A 24-tooth driver gear turns a 12-tooth driven gear. The driver turns 10 times. How many times does the driven gear turn?
  28. 28.⚙️ A 45-tooth driver gear turns a 15-tooth driven gear. The driver turns 3 times. How many times does the driven gear turn?
  29. 29.⚙️ An 8-tooth driver gear turns a 40-tooth driven gear. The driven gear turns 9 times. How many times did the driver turn?
  30. 30.⚙️ A motor makes 60 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?
  31. 31.⚙️ A 10-tooth gear drives a 20-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  32. 32.⚙️ A 32-tooth driver gear turns an 8-tooth driven gear. The driver turns 5 times. How many times does the driven gear turn?
  33. 33.⚙️ A 48-tooth driver gear turns a 12-tooth driven gear. The driver turns 9 times. How many times does the driven gear turn?
  34. 34.⚙️ An 8-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  35. 35.⚙️ A 15-tooth driver gear turns a 60-tooth driven gear. The driver turns 12 times. How many times does the driven gear turn?
  36. 36.⚙️ A 20-tooth driver gear turns a 60-tooth driven gear. The driver turns 24 times. How many times does the driven gear turn?
  37. 37.⚙️ A motor makes 80 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?
  38. 38.⚙️ A motor makes 100 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?
  39. 39.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driven gear turns 8 times. How many times did the driver turn?
  40. 40.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?

Answer key

  1. 40
  2. 3 times slower
  3. big (slow and strong)
  4. 5
  5. 100
  6. 40
  7. 60
  8. 3
  9. 4
  10. 90
  11. 40
  12. 10
  13. 18
  14. 5
  15. 15
  16. driver teeth
  17. 16
  18. 16
  19. 4
  20. 27
  21. 50
  22. 12
  23. 2
  24. 5
  25. 15
  26. 14
  27. 20
  28. 9
  29. 45
  30. 20
  31. 2
  32. 20
  33. 36
  34. 40
  35. 3
  36. 8
  37. 40
  38. 50
  39. 16
  40. 2

Free robotics lessons, practice and worksheets at talentjr.in/robotics-for-kids