← Light sensors and lines lesson New set →

Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 250 · 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.⬛ The threshold of a light sensor is … (a) the battery size (b) the wheel size (c) the black/white cut-off (d) the top speed
  2. 2.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 48. What is under the sensor? (a) the black line (b) the white floor
  3. 3.⬛ Why does a light sensor read a LOW number over a black line? (a) black soaks up light (b) black is hot (c) black is wet (d) black is loud
  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 light sensor reads below 50 over a black line and above 50 over the white floor. It reads 73. What is under the sensor? (a) the black line (b) the white floor
  6. 6.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  7. 7.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  8. 8.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 95. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  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.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  11. 11.🔦 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
  12. 12.🔦 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 white floor (b) the black line
  13. 13.🔦 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) neither sensor (c) the left sensor (d) both sensors
  14. 14.🔦 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
  15. 15.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 72. What is under the sensor? (a) the white floor (b) the black line
  16. 16.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  17. 17.🔦 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 white floor (b) the black line
  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.⬛ A reading below the threshold means the sensor is over … (a) water (b) black (c) the sky (d) white
  20. 20.🔦 A light sensor reads 20 over black and 80 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 80 and the right sensor reads 75. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) both sensors (d) neither sensor
  22. 22.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 53. What is under the sensor? (a) the black line (b) the white floor
  23. 23.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 95. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) neither sensor (d) both sensors
  24. 24.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 20. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) both sensors (d) the right sensor
  25. 25.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 61. What is under the sensor? (a) the black line (b) the white floor
  26. 26.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  27. 27.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  28. 28.⬛ 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 right sensor (d) under the left sensor
  29. 29.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 43. What is under the sensor? (a) the black line (b) the white floor
  30. 30.🔦 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
  31. 31.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 45. 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 90 and the right sensor reads 95. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) the left sensor (d) both sensors
  33. 33.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 40. What is under the sensor? (a) the black line (b) the white floor
  34. 34.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 79. What is under the sensor? (a) the black line (b) the white floor
  35. 35.🔦 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
  36. 36.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 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
  37. 37.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 and the right sensor reads 25. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) neither sensor (d) both sensors
  38. 38.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  39. 39.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 85 and the right sensor reads 90. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) both sensors (d) neither sensor
  40. 40.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?

Answer key

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

Free robotics lessons, practice and worksheets at talentjr.in/robotics-for-kids