← Gear ratio sums lesson New set →

Robotics Worksheet: Gear Ratio for Kids

Robotics lesson 14: Gear ratio sums · Set 173 · 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.🔢 To climb a steep ramp, a robot needs a gear ratio that is … (a) small (fast, weak) (b) never important (c) big (slow and strong) (d) zero
  2. 2.⚙️ A 12-tooth gear drives a 36-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  3. 3.⚙️ A 15-tooth gear drives a 30-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  4. 4.⚙️ A 10-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  5. 5.⚙️ A 12-tooth driver gear turns a 24-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  6. 6.🔢 A gear ratio of 3 (driven ÷ driver) means the driven gear turns … (a) 3 times faster (b) 3 times louder (c) 3 times bigger (d) 3 times slower
  7. 7.⚙️ A motor makes 80 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?
  8. 8.🔢 Gear ratio = driven teeth ÷ … (a) wheel size (b) number of gears (c) driver teeth (d) motor volts
  9. 9.⚙️ A motor makes 40 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 24-tooth driver gear turns a 12-tooth driven gear. The driver turns 1 time. How many times does the driven gear turn?
  11. 11.⚙️ A 36-tooth driver gear turns a 12-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  12. 12.⚙️ A 16-tooth driver gear turns an 8-tooth driven gear. The driver turns 6 times. How many times does the driven gear turn?
  13. 13.⚙️ A 20-tooth gear drives an 80-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  14. 14.⚙️ A 10-tooth gear drives a 40-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  15. 15.⚙️ A 15-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  16. 16.⚙️ An 8-tooth gear drives a 24-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  17. 17.⚙️ An 8-tooth driver gear must make the driven gear turn 4 times slower. How many teeth must the driven gear have?
  18. 18.⚙️ A 20-tooth driver gear turns a 40-tooth driven gear. The driven gear turns 9 times. How many times did the driver turn?
  19. 19.⚙️ A 40-tooth driver gear turns a 10-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  20. 20.⚙️ A 12-tooth driver gear turns a 48-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 5 times slower. How many teeth must the driven gear have?
  22. 22.⚙️ A 10-tooth driver gear must make the driven gear turn 2 times slower. How many teeth must the driven gear have?
  23. 23.⚙️ 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?
  24. 24.⚙️ A 20-tooth driver gear turns a 100-tooth driven gear. The driver turns 50 times. How many times does the driven gear turn?
  25. 25.⚙️ A 16-tooth driver gear turns an 8-tooth driven gear. The driver turns 9 times. How many times does the driven gear turn?
  26. 26.⚙️ A 10-tooth gear drives a 50-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  27. 27.⚙️ A 75-tooth driver gear turns a 15-tooth driven gear. The driver turns 8 times. How many times does the driven gear turn?
  28. 28.⚙️ A motor makes 20 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?
  29. 29.⚙️ A 15-tooth driver gear turns a 75-tooth driven gear. The driver turns 15 times. How many times does the driven gear turn?
  30. 30.⚙️ A 24-tooth driver gear turns a 12-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  31. 31.⚙️ A 12-tooth gear drives a 24-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  32. 32.⚙️ 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?
  33. 33.⚙️ A 20-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  34. 34.⚙️ A motor makes 440 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?
  35. 35.⚙️ A motor makes 150 turns a minute with a 10-tooth gear on it. That gear drives a 50-tooth gear. How many turns a minute does the 50-tooth gear make?
  36. 36.⚙️ An 8-tooth gear drives a 40-tooth gear. What is the gear ratio (driven teeth ÷ driver teeth)?
  37. 37.⚙️ A 12-tooth driver gear turns a 48-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  38. 38.⚙️ An 8-tooth driver gear turns a 16-tooth driven gear. The driver turns 4 times. How many times does the driven gear turn?
  39. 39.⚙️ A 12-tooth driver gear must make the driven gear turn 3 times slower. How many teeth must the driven gear have?
  40. 40.⚙️ A 10-tooth driver gear turns a 20-tooth driven gear. The driven gear turns 9 times. How many times did the driver turn?

Answer key

  1. big (slow and strong)
  2. 3
  3. 2
  4. 30
  5. 2
  6. 3 times slower
  7. 20
  8. driver teeth
  9. 20
  10. 2
  11. 18
  12. 12
  13. 4
  14. 4
  15. 60
  16. 3
  17. 32
  18. 18
  19. 16
  20. 5
  21. 75
  22. 20
  23. 90
  24. 10
  25. 18
  26. 5
  27. 40
  28. 10
  29. 3
  30. 8
  31. 2
  32. 80
  33. 60
  34. 110
  35. 30
  36. 5
  37. 1
  38. 2
  39. 36
  40. 18

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