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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 675 · 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.⬛ 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
  2. 2.⬛ The threshold of a light sensor is … (a) the black/white cut-off (b) the battery size (c) the wheel size (d) the top speed
  3. 3.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  4. 4.⬛ A reading below the threshold means the sensor is over … (a) white (b) the sky (c) black (d) water
  5. 5.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  6. 6.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 70. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the left sensor (d) the right sensor
  7. 7.🔦 A light sensor reads 10 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 53. 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 55. What is under the sensor? (a) the white floor (b) the black line
  10. 10.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  11. 11.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 63. What is under the sensor? (a) the white floor (b) the black line
  12. 12.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  13. 13.⬛ 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
  14. 14.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  15. 15.🔦 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 right sensor (b) the left sensor (c) both sensors (d) neither sensor
  16. 16.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 63. 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 45. What is under the sensor? (a) the black line (b) the white floor
  18. 18.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 75. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) both sensors (d) the left sensor
  19. 19.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 14. What is under the sensor? (a) the black line (b) the white floor
  20. 20.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 and the right sensor reads 35. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) the left sensor (d) both sensors
  21. 21.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 and the right sensor reads 65. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) the left sensor (d) neither sensor
  22. 22.🔦 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
  23. 23.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 62. What is under the sensor? (a) the white floor (b) the black line
  24. 24.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 65 and the right sensor reads 15. Which sensor is over the black line? (a) both sensors (b) the right sensor (c) the left sensor (d) neither sensor
  25. 25.🔦 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 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 10 and the right sensor reads 40. Which sensor is over the black line? (a) both sensors (b) the right sensor (c) the left sensor (d) neither sensor
  27. 27.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 75 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
  28. 28.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 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
  29. 29.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 55. What is under the sensor? (a) the white floor (b) the black line
  30. 30.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 95. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the left sensor (d) the right sensor
  31. 31.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 28. What is under the sensor? (a) the black line (b) the white floor
  32. 32.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 47. What is under the sensor? (a) the white floor (b) the black line
  33. 33.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 85 and the right sensor reads 65. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) both sensors (d) the right sensor
  34. 34.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 64. What is under the sensor? (a) the black line (b) the white floor
  35. 35.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 8. What is under the sensor? (a) the black line (b) the white floor
  36. 36.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 67. What is under the sensor? (a) the white floor (b) the black line
  37. 37.🔦 A light sensor reads 40 over black and 80 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 15 and the right sensor reads 15. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  39. 39.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 40. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  40. 40.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 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

Answer key

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

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