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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 722 · 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 reading below the threshold means the sensor is over … (a) water (b) black (c) white (d) the sky
  2. 2.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) under the right sensor (b) between the two sensors (c) under the left sensor (d) far behind it
  3. 3.⬛ The threshold of a light sensor is … (a) the top speed (b) the black/white cut-off (c) the wheel size (d) the battery size
  4. 4.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 36. What is under the sensor? (a) the black line (b) the white floor
  5. 5.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 53. What is under the sensor? (a) the black line (b) the white floor
  6. 6.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 25. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) neither sensor (d) both sensors
  7. 7.⬛ Why does a light sensor read a LOW number over a black line? (a) black is loud (b) black is wet (c) black is hot (d) black soaks up light
  8. 8.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 14. What is under the sensor? (a) the black line (b) the white floor
  9. 9.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 52. What is under the sensor? (a) the black line (b) the white floor
  10. 10.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  11. 11.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 27. 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 90 and the right sensor reads 10. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) the right sensor (d) both sensors
  13. 13.🔦 A light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  14. 14.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 43. What is under the sensor? (a) the white floor (b) the black line
  15. 15.🔦 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) neither sensor (d) both sensors
  16. 16.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 10. What is under the sensor? (a) the white floor (b) the black line
  17. 17.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 75 and the right sensor reads 85. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) both sensors (d) the left sensor
  18. 18.🔦 A light sensor reads 10 over black and 80 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 25. 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 80 and the right sensor reads 75. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  21. 21.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 79. What is under the sensor? (a) the black line (b) the white floor
  22. 22.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  23. 23.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  24. 24.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 and the right sensor reads 90. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) neither sensor (d) the left sensor
  25. 25.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  26. 26.🔦 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 white floor (b) the black line
  27. 27.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 56. What is under the sensor? (a) the white floor (b) the black line
  28. 28.🔦 A light sensor reads 30 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 33. What is under the sensor? (a) the white floor (b) the black line
  30. 30.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 22. What is under the sensor? (a) the white floor (b) the black line
  31. 31.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 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
  32. 32.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 13. What is under the sensor? (a) the black line (b) the white floor
  33. 33.🔦 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
  34. 34.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  35. 35.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 95. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  36. 36.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  37. 37.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 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
  38. 38.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 69. What is under the sensor? (a) the black line (b) the white floor
  39. 39.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 27. What is under the sensor? (a) the black line (b) the white floor
  40. 40.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 80. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the right sensor (d) the left sensor

Answer key

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

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