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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 157 · 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 70 and the right sensor reads 65. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  2. 2.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 29. What is under the sensor? (a) the white floor (b) the black line
  3. 3.🔦 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) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  4. 4.🔦 A light sensor reads 10 over black and 80 over white. A good threshold is halfway between them. What is it?
  5. 5.⬛ A reading below the threshold means the sensor is over … (a) the sky (b) white (c) black (d) water
  6. 6.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 85. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  7. 7.⬛ The threshold of a light sensor is … (a) the top speed (b) the wheel size (c) the black/white cut-off (d) the battery size
  8. 8.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) far behind it (b) under the right sensor (c) under the left sensor (d) between the two sensors
  9. 9.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  10. 10.🔦 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 black line (b) the white floor
  11. 11.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 54. What is under the sensor? (a) the black line (b) the white floor
  12. 12.🔦 A light sensor reads 40 over black and 60 over white. A good threshold is halfway between them. What is it?
  13. 13.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  14. 14.🔦 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 left sensor (c) both sensors (d) the right sensor
  15. 15.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 53. What is under the sensor? (a) the black line (b) the white floor
  16. 16.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  17. 17.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  18. 18.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 39. What is under the sensor? (a) the white floor (b) the black line
  19. 19.🔦 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 left sensor (b) the right sensor (c) both sensors (d) neither sensor
  20. 20.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 49. What is under the sensor? (a) the black line (b) the white floor
  21. 21.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  22. 22.⬛ Why does a light sensor read a LOW number over a black line? (a) black is loud (b) black is hot (c) black is wet (d) black soaks up light
  23. 23.🔦 A light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  24. 24.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  25. 25.🔦 A light sensor reads 30 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 35. What is under the sensor? (a) the black line (b) the white floor
  27. 27.🔦 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 black line (b) the white floor
  28. 28.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 35. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  29. 29.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  30. 30.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 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
  31. 31.🔦 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
  32. 32.🔦 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
  33. 33.🔦 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 white floor (b) the black line
  34. 34.🔦 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
  35. 35.🔦 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 white floor (b) the black line
  36. 36.🔦 A light sensor reads 10 over black and 90 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 20 and the right sensor reads 60. 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 15. 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 23. What is under the sensor? (a) the white floor (b) the black line

Answer key

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

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