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Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 269 · 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 below 30 over a black line and above 30 over the white floor. It reads 13. What is under the sensor? (a) the black line (b) the white floor
  2. 2.⬛ The threshold of a light sensor is … (a) the battery size (b) the wheel size (c) the top speed (d) the black/white cut-off
  3. 3.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 45. What is under the sensor? (a) the black line (b) the white floor
  4. 4.🔦 A light sensor reads 40 over black and 70 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) black (b) white (c) the sky (d) water
  6. 6.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 6. What is under the sensor? (a) the white floor (b) the black line
  7. 7.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 36. What is under the sensor? (a) the black line (b) the white floor
  8. 8.🔦 A light sensor reads 30 over black and 80 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 73. What is under the sensor? (a) the white floor (b) the black line
  10. 10.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  11. 11.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  12. 12.🔦 A light sensor reads 10 over black and 80 over white. A good threshold is halfway between them. What is it?
  13. 13.🔦 A light sensor reads 40 over black and 60 over white. A good threshold is halfway between them. What is it?
  14. 14.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  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.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) under the right sensor (b) under the left sensor (c) between the two sensors (d) far behind it
  17. 17.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 95. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) both sensors (d) the left sensor
  18. 18.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 10. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) neither sensor (d) both sensors
  19. 19.🔦 A light sensor reads 20 over black and 80 over white. A good threshold is halfway between them. What is it?
  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 85. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) the right sensor (d) neither sensor
  21. 21.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 11. What is under the sensor? (a) the black line (b) the white floor
  22. 22.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 37. What is under the sensor? (a) the black line (b) the white floor
  23. 23.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 9. What is under the sensor? (a) the white floor (b) the black line
  24. 24.⬛ Why does a light sensor read a LOW number over a black line? (a) black is loud (b) black is wet (c) black soaks up light (d) black is hot
  25. 25.🔦 A light sensor reads 40 over black and 80 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 51. What is under the sensor? (a) the black line (b) the white floor
  27. 27.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 42. What is under the sensor? (a) the white floor (b) the black line
  28. 28.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 58. What is under the sensor? (a) the black line (b) the white floor
  29. 29.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 40. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) neither sensor (d) the left sensor
  30. 30.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  31. 31.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  32. 32.🔦 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
  33. 33.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 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
  34. 34.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 38. What is under the sensor? (a) the black line (b) the white floor
  35. 35.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 70. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  36. 36.🔦 A light sensor reads 20 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 15 and the right sensor reads 85. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) the right sensor (d) neither sensor
  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 75. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) neither sensor (d) the left sensor
  39. 39.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 85. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) neither sensor (d) the right sensor
  40. 40.🔦 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

Answer key

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

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