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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 991 · 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 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
  2. 2.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  3. 3.🔦 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
  4. 4.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 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
  5. 5.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 and the right sensor reads 15. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) neither sensor (d) both sensors
  6. 6.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  7. 7.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 43. What is under the sensor? (a) the black line (b) the white floor
  8. 8.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  9. 9.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 19. What is under the sensor? (a) the white floor (b) the black line
  10. 10.🔦 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
  11. 11.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  12. 12.⬛ Why does a light sensor read a LOW number over a black line? (a) black soaks up light (b) black is loud (c) black is hot (d) black is wet
  13. 13.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 17. What is under the sensor? (a) the black line (b) the white floor
  14. 14.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 39. What is under the sensor? (a) the black line (b) the white floor
  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 85. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) neither sensor (d) the left sensor
  16. 16.🔦 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 black line (b) the white floor
  17. 17.🔦 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
  18. 18.⬛ The threshold of a light sensor is … (a) the wheel size (b) the battery size (c) the top speed (d) the black/white cut-off
  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 75. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the right sensor (d) the left sensor
  20. 20.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 69. What is under the sensor? (a) the black line (b) the white floor
  21. 21.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 74. What is under the sensor? (a) the white floor (b) the black line
  22. 22.🔦 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 black line (b) the white floor
  23. 23.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  24. 24.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) between the two sensors (b) far behind it (c) under the right sensor (d) under the left sensor
  25. 25.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 75. What is under the sensor? (a) the black line (b) the white floor
  26. 26.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 40. Which sensor is over the black line? (a) both sensors (b) the right sensor (c) neither sensor (d) the left sensor
  27. 27.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 40. What is under the sensor? (a) the white floor (b) the black line
  28. 28.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 and the right sensor reads 10. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the right sensor (d) the left sensor
  29. 29.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 10. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) the left sensor (d) both sensors
  30. 30.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 30 and the right sensor reads 75. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) neither sensor (d) the right sensor
  31. 31.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 65. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  32. 32.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 46. What is under the sensor? (a) the white floor (b) the black line
  33. 33.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 58. What is under the sensor? (a) the black line (b) the white floor
  34. 34.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 80. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the left sensor (d) the right sensor
  35. 35.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  36. 36.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 21. What is under the sensor? (a) the white floor (b) the black line
  37. 37.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 65 and the right sensor reads 75. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the left sensor (d) the right sensor
  38. 38.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  39. 39.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 and the right sensor reads 10. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  40. 40.🔦 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

Answer key

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

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