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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 933 · 40 questions
TalentJR

Robot tip (Below the threshold is black): Reading below the threshold → black; above → white. Threshold = (black reading + white reading) ÷ 2. Two sensors: the one that reads black is over the line; both white → the line is between them.

NameDateTime takenScore ___ / 40
  1. 1.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 30 and the right sensor reads 70. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) the left sensor (d) both sensors
  2. 2.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) under the right sensor (b) under the left sensor (c) between the two sensors (d) far behind it
  3. 3.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  4. 4.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 63. What is under the sensor? (a) the black line (b) the white floor
  5. 5.⬛ Why does a light sensor read a LOW number over a black line? (a) black is hot (b) black soaks up light (c) black is loud (d) black is wet
  6. 6.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  7. 7.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 47. What is under the sensor? (a) the black line (b) the white floor
  8. 8.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  9. 9.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 50. What is under the sensor? (a) the white floor (b) the black line
  10. 10.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  11. 11.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 42. What is under the sensor? (a) the white floor (b) the black line
  12. 12.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 75 and the right sensor reads 10. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  13. 13.⬛ The threshold of a light sensor is … (a) the battery size (b) the wheel size (c) the black/white cut-off (d) the top speed
  14. 14.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  15. 15.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 27. What is under the sensor? (a) the white floor (b) the black line
  16. 16.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 34. What is under the sensor? (a) the black line (b) the white floor
  17. 17.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 70. What is under the sensor? (a) the black line (b) the white floor
  18. 18.🔦 A light sensor reads 20 over black and 80 over white. A good threshold is halfway between them. What is it?
  19. 19.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 46. What is under the sensor? (a) the white floor (b) the black line
  20. 20.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 85. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) the left sensor (d) both sensors
  21. 21.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 55. What is under the sensor? (a) the white floor (b) the black line
  22. 22.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 18. What is under the sensor? (a) the white floor (b) the black line
  23. 23.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  24. 24.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 24. What is under the sensor? (a) the black line (b) the white floor
  25. 25.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  26. 26.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 29. What is under the sensor? (a) the white floor (b) the black line
  27. 27.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 75. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) neither sensor (d) both sensors
  28. 28.🔦 A light sensor reads 40 over black and 60 over white. A good threshold is halfway between them. What is it?
  29. 29.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 50. What is under the sensor? (a) the white floor (b) the black line
  30. 30.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 20. What is under the sensor? (a) the white floor (b) the black line
  31. 31.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 28. What is under the sensor? (a) the white floor (b) the black line
  32. 32.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  33. 33.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 84. What is under the sensor? (a) the white floor (b) the black line
  34. 34.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 90 and the right sensor reads 70. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) neither sensor (d) the left sensor
  35. 35.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 36. What is under the sensor? (a) the white floor (b) the black line
  36. 36.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 42. What is under the sensor? (a) the black line (b) the white floor
  37. 37.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 30 and the right sensor reads 85. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  38. 38.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  39. 39.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 42. What is under the sensor? (a) the white floor (b) the black line
  40. 40.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 6. What is under the sensor? (a) the white floor (b) the black line

Answer key

  1. the left sensor
  2. between the two sensors
  3. 40
  4. the white floor
  5. black soaks up light
  6. 60
  7. the white floor
  8. 50
  9. the white floor
  10. 55
  11. the black line
  12. the right sensor
  13. the black/white cut-off
  14. 60
  15. the black line
  16. the black line
  17. the white floor
  18. 50
  19. the white floor
  20. the left sensor
  21. the white floor
  22. the black line
  23. 50
  24. the black line
  25. 40
  26. the black line
  27. neither sensor
  28. 50
  29. the white floor
  30. the black line
  31. the black line
  32. 35
  33. the white floor
  34. neither sensor
  35. the black line
  36. the white floor
  37. the left sensor
  38. 55
  39. the black line
  40. the black line

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