← Gear ratio sums lesson New set →

Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 86 · 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 60-tooth driver gear turns a 20-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  2. 2.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) big (slow and strong) (b) zero (c) small (fast, weak) (d) never important
  3. 3.⚙️ A 20-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  4. 4.⚙️ A 12-tooth driver gear turns a 48-tooth driven gear. The driver turns 20 times. How many times does the driven gear turn?
  5. 5.⚙️ A 48-tooth driver gear turns a 12-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  6. 6.⚙️ An 8-tooth gear drives a 24-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  7. 7.⚙️ A motor makes 80 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?
  8. 8.⚙️ A 12-tooth gear drives a 36-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  9. 9.⚙️ A motor makes 40 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?
  10. 10.⚙️ A 10-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  11. 11.⚙️ A 20-tooth driver gear turns a 10-tooth driven gear. The driver turns 7 times. How many times does the driven gear turn?
  12. 12.⚙️ A 32-tooth driver gear turns an 8-tooth driven gear. The driver turns 9 times. How many times does the driven gear turn?
  13. 13.⚙️ An 8-tooth gear drives a 32-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  14. 14.⚙️ A 12-tooth driver gear turns a 24-tooth driven gear. The driven gear turns 9 times. How many times did the driver turn?
  15. 15.🔢 A gear ratio of 3 (driven ÷ driver) means the driven gear turns … (a) 3 times bigger (b) 3 times louder (c) 3 times slower (d) 3 times faster
  16. 16.🔢 Gear ratio = driven teeth ÷ … (a) wheel size (b) driver teeth (c) motor volts (d) number of gears
  17. 17.⚙️ A 15-tooth driver gear turns a 30-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  18. 18.⚙️ An 8-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  19. 19.⚙️ An 80-tooth driver gear turns a 20-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  20. 20.⚙️ A 15-tooth driver gear turns a 30-tooth driven gear. The driver turns 20 times. How many times does the driven gear turn?
  21. 21.⚙️ A 15-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  22. 22.⚙️ An 8-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  23. 23.⚙️ A motor makes 120 turns a minute with a 15-tooth gear on it. That gear drives a 60-tooth gear. How many turns a minute does the 60-tooth gear make?
  24. 24.⚙️ A 75-tooth driver gear turns a 15-tooth driven gear. The driver turns 7 times. How many times does the driven gear turn?
  25. 25.⚙️ A 40-tooth driver gear turns a 20-tooth driven gear. The driver turns 3 times. How many times does the driven gear turn?
  26. 26.⚙️ A 20-tooth driver gear turns a 60-tooth driven gear. The driver turns 30 times. How many times does the driven gear turn?
  27. 27.⚙️ A 15-tooth driver gear turns a 60-tooth driven gear. The driven gear turns 8 times. How many times did the driver turn?
  28. 28.⚙️ An 8-tooth gear drives a 16-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  29. 29.⚙️ A 24-tooth driver gear turns a 12-tooth driven gear. The driver turns 2 times. How many times does the driven gear turn?
  30. 30.⚙️ A 10-tooth driver gear turns a 20-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  31. 31.⚙️ An 8-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  32. 32.⚙️ An 8-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  33. 33.⚙️ A 36-tooth driver gear turns a 12-tooth driven gear. The driver turns 2 times. How many times does the driven gear turn?
  34. 34.⚙️ 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?
  35. 35.⚙️ A 20-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  36. 36.⚙️ A 50-tooth driver gear turns a 10-tooth driven gear. The driver turns 9 times. How many times does the driven gear turn?
  37. 37.⚙️ A 12-tooth gear drives a 24-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  38. 38.⚙️ A motor makes 120 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?
  39. 39.⚙️ 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?
  40. 40.⚙️ A 40-tooth driver gear turns a 10-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?

Answer key

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

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