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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 181 · 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 reading below the threshold means the sensor is over … (a) water (b) white (c) the sky (d) black
  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 robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 20. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) the right sensor (d) neither sensor
  4. 4.🔦 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
  5. 5.🔦 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 black line (b) the white floor
  6. 6.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 34. What is under the sensor? (a) the black line (b) the white floor
  7. 7.⬛ The threshold of a light sensor is … (a) the battery size (b) the top speed (c) the wheel size (d) the black/white cut-off
  8. 8.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  9. 9.🔦 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
  10. 10.⬛ Why does a light sensor read a LOW number over a black line? (a) black is hot (b) black is wet (c) black soaks up light (d) black is loud
  11. 11.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 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
  12. 12.🔦 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) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  13. 13.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  14. 14.🔦 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
  15. 15.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  16. 16.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 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
  17. 17.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  18. 18.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 and the right sensor reads 20. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  19. 19.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 57. What is under the sensor? (a) the white floor (b) the black line
  20. 20.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  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 85. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) neither sensor (d) both sensors
  22. 22.🔦 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) neither sensor (b) the left sensor (c) both sensors (d) the right sensor
  23. 23.🔦 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) neither sensor (b) both sensors (c) the right sensor (d) the left sensor
  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 white floor (b) the black line
  25. 25.🔦 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
  26. 26.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 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
  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 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
  29. 29.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 32. 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 35 and the right sensor reads 40. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) the left sensor (d) neither sensor
  31. 31.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) between the two sensors (b) under the left sensor (c) under the right sensor (d) far behind it
  32. 32.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 7. What is under the sensor? (a) the white floor (b) the black line
  33. 33.🔦 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 white floor (b) the black line
  34. 34.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  35. 35.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  36. 36.🔦 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 black line (b) the white floor
  37. 37.🔦 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 white floor (b) the black line
  38. 38.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 63. What is under the sensor? (a) the black line (b) the white floor
  39. 39.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 39. What is under the sensor? (a) the white floor (b) the black line
  40. 40.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 75. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) neither sensor (d) the right sensor

Answer key

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

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