← Light sensors and lines lesson New set →

Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 934 · 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 50 over a black line and above 50 over the white floor. It reads 59. What is under the sensor? (a) the black line (b) the white floor
  2. 2.🔦 A light sensor reads 30 over black and 60 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 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
  4. 4.⬛ 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
  5. 5.⬛ A reading below the threshold means the sensor is over … (a) the sky (b) water (c) white (d) black
  6. 6.⬛ The threshold of a light sensor is … (a) the wheel size (b) the battery size (c) the top speed (d) the black/white cut-off
  7. 7.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 39. What is under the sensor? (a) the black line (b) the white floor
  8. 8.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 90. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) the right sensor (d) both sensors
  9. 9.🔦 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) neither sensor (b) the right sensor (c) both sensors (d) the left sensor
  10. 10.🔦 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
  11. 11.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  12. 12.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 75 and the right sensor reads 15. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the left sensor (d) the right sensor
  13. 13.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 15. What is under the sensor? (a) the black line (b) the white floor
  14. 14.🔦 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 black line (b) the white floor
  15. 15.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 and the right sensor reads 25. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  16. 16.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 68. What is under the sensor? (a) the black line (b) the white floor
  17. 17.⬛ Why does a light sensor read a LOW number over a black line? (a) black is hot (b) black soaks up light (c) black is loud (d) black is wet
  18. 18.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 90 and the right sensor reads 10. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) the left sensor (d) both sensors
  19. 19.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 83. What is under the sensor? (a) the black line (b) the white floor
  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 light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  22. 22.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  23. 23.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 74. What is under the sensor? (a) the black line (b) the white floor
  24. 24.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  25. 25.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  26. 26.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 65. What is under the sensor? (a) the white floor (b) the black line
  27. 27.🔦 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 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 23. What is under the sensor? (a) the white floor (b) the black line
  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 15. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  30. 30.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 60. Which sensor is over the black line? (a) both sensors (b) the right sensor (c) neither sensor (d) the left sensor
  31. 31.🔦 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 black line (b) the white floor
  32. 32.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  33. 33.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 43. What is under the sensor? (a) the black line (b) the white floor
  34. 34.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 and the right sensor reads 10. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the left sensor (d) the right sensor
  35. 35.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 52. What is under the sensor? (a) the black line (b) the white floor
  36. 36.🔦 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 white floor (b) the black line
  37. 37.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 66. What is under the sensor? (a) the black line (b) the white floor
  38. 38.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 58. What is under the sensor? (a) the black line (b) the white floor
  39. 39.🔦 A light sensor reads 10 over black and 80 over white. A good threshold is halfway between them. What is it?
  40. 40.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 45. What is under the sensor? (a) the white floor (b) the black line

Answer key

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

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