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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 870 · 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 60 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
  2. 2.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  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 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  5. 5.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 75 and the right sensor reads 30. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) both sensors (d) neither sensor
  6. 6.🔦 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 white floor (b) the black line
  7. 7.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  8. 8.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 16. 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 26. What is under the sensor? (a) the black line (b) the white floor
  10. 10.🔦 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 black line (b) the white floor
  11. 11.⬛ The threshold of a light sensor is … (a) the wheel size (b) the battery size (c) the black/white cut-off (d) the top speed
  12. 12.🔦 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
  13. 13.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) under the left sensor (b) under the right sensor (c) between the two sensors (d) far behind it
  14. 14.⬛ Why does a light sensor read a LOW number over a black line? (a) black is loud (b) black soaks up light (c) black is hot (d) black is wet
  15. 15.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  16. 16.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  17. 17.🔦 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) both sensors (b) neither sensor (c) the left sensor (d) the right sensor
  18. 18.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  19. 19.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 65 and the right sensor reads 60. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  20. 20.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 75. Which sensor is over the black line? (a) both sensors (b) the right sensor (c) neither sensor (d) the left sensor
  21. 21.🔦 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) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  22. 22.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  23. 23.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 53. What is under the sensor? (a) the white floor (b) the black line
  24. 24.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  25. 25.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  26. 26.🔦 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
  27. 27.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 20. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the right sensor (d) the left sensor
  28. 28.🔦 A light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  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 below 40 over a black line and above 40 over the white floor. It reads 48. What is under the sensor? (a) the white floor (b) the black line
  31. 31.🔦 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 black line (b) the white floor
  32. 32.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 5. What is under the sensor? (a) the white floor (b) the black line
  33. 33.🔦 A light sensor reads 20 over black and 80 over white. A good threshold is halfway between them. What is it?
  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 40. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) both sensors (d) neither sensor
  35. 35.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 48. What is under the sensor? (a) the black line (b) the white floor
  36. 36.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 90. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) the left sensor (d) neither sensor
  37. 37.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  38. 38.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 90. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  39. 39.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  40. 40.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 and the right sensor reads 60. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) neither sensor (d) the right sensor

Answer key

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

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