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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 915 · 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 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  2. 2.⬛ A reading below the threshold means the sensor is over … (a) the sky (b) white (c) black (d) water
  3. 3.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 75 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
  4. 4.🔦 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 white floor (b) the black line
  5. 5.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) far behind it (b) under the left sensor (c) between the two sensors (d) under the right sensor
  6. 6.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 30. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) the right sensor (d) both sensors
  7. 7.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 and the right sensor reads 95. Which sensor is over the black line? (a) the left sensor (b) neither 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 38. What is under the sensor? (a) the black line (b) the white floor
  9. 9.🔦 A light sensor reads 10 over black and 90 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 36. What is under the sensor? (a) the white floor (b) the black line
  11. 11.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  12. 12.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 40. What is under the sensor? (a) the black line (b) the white floor
  13. 13.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 51. What is under the sensor? (a) the black line (b) the white floor
  14. 14.🔦 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) both sensors (b) the left sensor (c) neither sensor (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 85. What is under the sensor? (a) the white floor (b) the black line
  16. 16.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 and the right sensor reads 85. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the right sensor (d) the left sensor
  17. 17.🔦 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 black line (b) the white floor
  18. 18.🔦 A light sensor reads 40 over black and 60 over white. A good threshold is halfway between them. What is it?
  19. 19.⬛ Why does a light sensor read a LOW number over a black line? (a) black is wet (b) black is loud (c) black soaks up light (d) black is hot
  20. 20.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 26. What is under the sensor? (a) the white floor (b) the black line
  21. 21.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 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
  22. 22.⬛ The threshold of a light sensor is … (a) the black/white cut-off (b) the top speed (c) the battery size (d) the wheel size
  23. 23.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 59. What is under the sensor? (a) the white floor (b) the black line
  24. 24.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 44. What is under the sensor? (a) the black line (b) the white floor
  25. 25.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 54. What is under the sensor? (a) the black line (b) the white floor
  26. 26.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  27. 27.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 65 and the right sensor reads 80. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) neither sensor (d) the right sensor
  28. 28.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  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 40. 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 35 and the right sensor reads 10. 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 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  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 30. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  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 black line (b) the white floor
  34. 34.🔦 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 white floor (b) the black line
  35. 35.🔦 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 white floor (b) the black line
  36. 36.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 35. What is under the sensor? (a) the white floor (b) the black line
  37. 37.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  38. 38.🔦 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
  39. 39.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 37. What is under the sensor? (a) the white floor (b) the black line
  40. 40.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 33. What is under the sensor? (a) the white floor (b) the black line

Answer key

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

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