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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 923 · 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 80 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 81. What is under the sensor? (a) the white floor (b) the black line
  3. 3.⬛ A reading below the threshold means the sensor is over … (a) white (b) black (c) water (d) the sky
  4. 4.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 31. What is under the sensor? (a) the white floor (b) the black line
  5. 5.🔦 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
  6. 6.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 75. What is under the sensor? (a) the black line (b) the white floor
  7. 7.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  8. 8.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) under the left sensor (b) between the two sensors (c) under the right sensor (d) far behind it
  9. 9.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 20. What is under the sensor? (a) the black line (b) the white floor
  10. 10.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 and the right sensor reads 20. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  11. 11.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 95. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) neither sensor (d) the left sensor
  12. 12.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 54. What is under the sensor? (a) the white floor (b) the black line
  13. 13.⬛ Why does a light sensor read a LOW number over a black line? (a) black is wet (b) black is loud (c) black soaks up light (d) black is hot
  14. 14.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  15. 15.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  16. 16.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 40. What is under the sensor? (a) the white floor (b) the black line
  17. 17.⬛ The threshold of a light sensor is … (a) the battery size (b) the black/white cut-off (c) the top speed (d) the wheel size
  18. 18.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 80. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) neither sensor (d) the right sensor
  19. 19.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 25. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  20. 20.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 30. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) both sensors (d) neither sensor
  21. 21.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 17. 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 10 and the right sensor reads 30. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) the right sensor (d) both sensors
  23. 23.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 90 and the right sensor reads 25. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  24. 24.🔦 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
  25. 25.🔦 A light sensor reads 40 over black and 60 over white. A good threshold is halfway between them. What is it?
  26. 26.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 90 and the right sensor reads 60. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) the left sensor (d) both sensors
  27. 27.🔦 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) the right sensor (c) the left sensor (d) both sensors
  28. 28.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 51. What is under the sensor? (a) the white floor (b) the black line
  29. 29.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  30. 30.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  31. 31.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  32. 32.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 30. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the right sensor (d) the left sensor
  33. 33.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 65. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) both sensors (d) neither sensor
  34. 34.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 65. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) neither sensor (d) both sensors
  35. 35.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  36. 36.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 32. What is under the sensor? (a) the black line (b) the white floor
  37. 37.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 68. What is under the sensor? (a) the black line (b) the white floor
  38. 38.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  39. 39.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 82. What is under the sensor? (a) the white floor (b) the black line
  40. 40.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?

Answer key

  1. 45
  2. the white floor
  3. black
  4. the black line
  5. the white floor
  6. the white floor
  7. 40
  8. between the two sensors
  9. the black line
  10. both sensors
  11. the left sensor
  12. the white floor
  13. black soaks up light
  14. 35
  15. 55
  16. the black line
  17. the black/white cut-off
  18. neither sensor
  19. both sensors
  20. the right sensor
  21. the black line
  22. both sensors
  23. the right sensor
  24. the black line
  25. 50
  26. neither sensor
  27. both sensors
  28. the black line
  29. 60
  30. 50
  31. 65
  32. both sensors
  33. the left sensor
  34. neither sensor
  35. 45
  36. the black line
  37. the white floor
  38. 60
  39. the white floor
  40. 45

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