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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 684 · 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 light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  2. 2.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 80. What is under the sensor? (a) the black line (b) the white floor
  3. 3.⬛ A reading below the threshold means the sensor is over … (a) water (b) white (c) the sky (d) black
  4. 4.🔦 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 black line (b) the white floor
  5. 5.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  6. 6.🔦 A light sensor reads 40 over black and 60 over white. A good threshold is halfway between them. What is it?
  7. 7.⬛ The threshold of a light sensor is … (a) the black/white cut-off (b) the battery size (c) the wheel size (d) the top speed
  8. 8.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 26. What is under the sensor? (a) the white floor (b) the black line
  9. 9.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 7. What is under the sensor? (a) the white floor (b) the black line
  10. 10.⬛ Why does a light sensor read a LOW number over a black line? (a) black is wet (b) black soaks up light (c) black is loud (d) black is hot
  11. 11.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 36. 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 85 and the right sensor reads 60. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) both sensors (d) neither sensor
  13. 13.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  14. 14.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  15. 15.⬛ 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) far behind it (d) between the two sensors
  16. 16.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  17. 17.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 71. What is under the sensor? (a) the black line (b) the white floor
  18. 18.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  19. 19.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 34. What is under the sensor? (a) the white floor (b) the black line
  20. 20.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  21. 21.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 61. What is under the sensor? (a) the white floor (b) the black line
  22. 22.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 90 and the right sensor reads 65. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the left sensor (d) the right sensor
  23. 23.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 37. What is under the sensor? (a) the black line (b) the white floor
  24. 24.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 33. What is under the sensor? (a) the white floor (b) the black line
  25. 25.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 20. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) neither sensor (d) both sensors
  26. 26.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 60. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the left sensor (d) the right sensor
  27. 27.🔦 A light sensor reads 10 over black and 80 over white. A good threshold is halfway between them. What is it?
  28. 28.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 41. What is under the sensor? (a) the white floor (b) the black line
  29. 29.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  30. 30.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  31. 31.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 70. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) the left sensor (d) both sensors
  32. 32.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 15. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the left sensor (d) the right sensor
  33. 33.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 and the right sensor reads 35. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) neither sensor (d) both sensors
  34. 34.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 85 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
  35. 35.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 16. What is under the sensor? (a) the white floor (b) the black line
  36. 36.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 35. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) both sensors (d) the left sensor
  37. 37.🔦 A light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  38. 38.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 22. What is under the sensor? (a) the black line (b) the white floor
  39. 39.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 25. What is under the sensor? (a) the black line (b) the white floor
  40. 40.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 15. What is under the sensor? (a) the black line (b) the white floor

Answer key

  1. 35
  2. the white floor
  3. black
  4. the black line
  5. 50
  6. 50
  7. the black/white cut-off
  8. the black line
  9. the black line
  10. black soaks up light
  11. the black line
  12. neither sensor
  13. 45
  14. 55
  15. between the two sensors
  16. 40
  17. the white floor
  18. 60
  19. the black line
  20. 40
  21. the white floor
  22. neither sensor
  23. the black line
  24. the white floor
  25. the right sensor
  26. the left sensor
  27. 45
  28. the black line
  29. 45
  30. 55
  31. the left sensor
  32. both sensors
  33. both sensors
  34. neither sensor
  35. the black line
  36. both sensors
  37. 55
  38. the black line
  39. the black line
  40. the black line

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