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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 4 · 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 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
  2. 2.🔦 A light sensor reads 40 over black and 60 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) black (c) the sky (d) white
  4. 4.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  5. 5.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) far behind it (b) between the two sensors (c) under the left sensor (d) under the right sensor
  6. 6.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  7. 7.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 65 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
  8. 8.🔦 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
  9. 9.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 24. What is under the sensor? (a) the black line (b) the white floor
  10. 10.⬛ Why does a light sensor read a LOW number over a black line? (a) black is wet (b) black is hot (c) black soaks up light (d) black is loud
  11. 11.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 24. 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 10 and the right sensor reads 25. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) neither sensor (d) the right sensor
  13. 13.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 57. What is under the sensor? (a) the white floor (b) the black line
  14. 14.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 and the right sensor reads 95. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) neither sensor (d) both sensors
  15. 15.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  16. 16.🔦 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 black line (b) the white floor
  17. 17.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 65. What is under the sensor? (a) the black line (b) the white floor
  18. 18.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 50. What is under the sensor? (a) the black line (b) the white floor
  19. 19.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  20. 20.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  21. 21.🔦 A light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  22. 22.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  23. 23.🔦 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
  24. 24.⬛ The threshold of a light sensor is … (a) the wheel size (b) the black/white cut-off (c) the battery size (d) the top speed
  25. 25.🔦 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 white floor (b) the black line
  26. 26.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 15. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) both sensors (d) the left sensor
  27. 27.🔦 A light sensor reads 10 over black and 80 over white. A good threshold is halfway between them. What is it?
  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 75. Which sensor is over the black line? (a) both sensors (b) the right sensor (c) neither 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 35 and the right sensor reads 15. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) both sensors (d) neither sensor
  30. 30.🔦 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 right sensor (b) neither sensor (c) both sensors (d) the left sensor
  31. 31.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 47. What is under the sensor? (a) the white floor (b) the black line
  32. 32.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 70 and the right sensor reads 75. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  33. 33.🔦 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
  34. 34.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 37. 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 53. What is under the sensor? (a) the white floor (b) the black line
  36. 36.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 85. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the left sensor (d) the right sensor
  37. 37.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 70 and the right sensor reads 10. 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 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
  39. 39.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 and the right sensor reads 70. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  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. 50
  3. black
  4. 40
  5. between the two sensors
  6. 55
  7. the right sensor
  8. the black line
  9. the black line
  10. black soaks up light
  11. the black line
  12. both sensors
  13. the black line
  14. the left sensor
  15. 45
  16. the white floor
  17. the white floor
  18. the white floor
  19. 50
  20. 60
  21. 55
  22. 65
  23. the black line
  24. the black/white cut-off
  25. the white floor
  26. both sensors
  27. 45
  28. the left sensor
  29. both sensors
  30. neither sensor
  31. the black line
  32. neither sensor
  33. the white floor
  34. the black line
  35. the black line
  36. neither sensor
  37. the right sensor
  38. the white floor
  39. the left sensor
  40. the black line

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