← Gear ratio sums lesson New set →

Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 17 · 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 30-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  2. 2.⚙️ A 15-tooth driver gear turns a 75-tooth driven gear. The driver turns 10 times. How many times does the driven gear turn?
  3. 3.⚙️ A 15-tooth driver gear turns a 45-tooth driven gear. The driven gear turns 3 times. How many times did the driver turn?
  4. 4.⚙️ A motor makes 320 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?
  5. 5.⚙️ A 10-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  6. 6.⚙️ A 100-tooth driver gear turns a 20-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  7. 7.⚙️ A 12-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  8. 8.⚙️ An 8-tooth gear drives a 16-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  9. 9.⚙️ A 60-tooth driver gear turns a 20-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  10. 10.⚙️ A motor makes 100 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?
  11. 11.⚙️ A 15-tooth driver gear turns a 75-tooth driven gear. The driven gear turns 6 times. How many times did the driver turn?
  12. 12.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  13. 13.⚙️ An 8-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  14. 14.⚙️ A 20-tooth driver gear turns a 100-tooth driven gear. The driver turns 20 times. How many times does the driven gear turn?
  15. 15.🔢 Gear ratio = driven teeth ÷ … (a) wheel size (b) number of gears (c) driver teeth (d) motor volts
  16. 16.⚙️ A 12-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  17. 17.⚙️ An 8-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  18. 18.⚙️ A motor makes 300 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?
  19. 19.⚙️ A 15-tooth driver gear turns a 75-tooth driven gear. The driver turns 35 times. How many times does the driven gear turn?
  20. 20.⚙️ A 20-tooth gear drives a 100-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  21. 21.⚙️ A 45-tooth driver gear turns a 15-tooth driven gear. The driver turns 7 times. How many times does the driven gear turn?
  22. 22.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) zero (b) small (fast, weak) (c) big (slow and strong) (d) never important
  23. 23.⚙️ A 12-tooth driver gear turns a 48-tooth driven gear. The driven gear turns 1 time. How many times did the driver turn?
  24. 24.⚙️ A 20-tooth driver gear turns a 40-tooth driven gear. The driver turns 18 times. How many times does the driven gear turn?
  25. 25.⚙️ A 12-tooth gear drives a 36-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  26. 26.⚙️ A 10-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  27. 27.⚙️ A 12-tooth driver gear turns a 24-tooth driven gear. The driver turns 10 times. How many times does the driven gear turn?
  28. 28.⚙️ A motor makes 30 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?
  29. 29.⚙️ A 10-tooth driver gear turns a 40-tooth driven gear. The driver turns 16 times. How many times does the driven gear turn?
  30. 30.⚙️ An 8-tooth driver gear must make the driven gear turn 5 times slower. How many teeth must the driven gear have?
  31. 31.⚙️ A 50-tooth driver gear turns a 10-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  32. 32.⚙️ 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?
  33. 33.⚙️ A 40-tooth driver gear turns an 8-tooth driven gear. The driver turns 2 times. How many times does the driven gear turn?
  34. 34.⚙️ A motor makes 200 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?
  35. 35.⚙️ An 8-tooth driver gear turns a 40-tooth driven gear. The driver turns 15 times. How many times does the driven gear turn?
  36. 36.⚙️ A 12-tooth gear drives a 48-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  37. 37.⚙️ A 10-tooth driver gear turns a 40-tooth driven gear. The driven gear turns 8 times. How many times did the driver turn?
  38. 38.⚙️ A 15-tooth gear drives a 75-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  39. 39.⚙️ An 80-tooth driver gear turns a 20-tooth driven gear. The driver turns 7 times. How many times does the driven gear turn?
  40. 40.⚙️ An 80-tooth driver gear turns a 20-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?

Answer key

  1. 2
  2. 2
  3. 9
  4. 80
  5. 30
  6. 30
  7. 36
  8. 2
  9. 18
  10. 50
  11. 30
  12. 3
  13. 16
  14. 4
  15. driver teeth
  16. 48
  17. 24
  18. 60
  19. 7
  20. 5
  21. 21
  22. big (slow and strong)
  23. 4
  24. 9
  25. 3
  26. 20
  27. 5
  28. 10
  29. 4
  30. 40
  31. 30
  32. 40
  33. 10
  34. 50
  35. 3
  36. 4
  37. 32
  38. 5
  39. 28
  40. 32

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