← Light sensors and lines lesson New set →

Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 498 · 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 60 over a black line and above 60 over the white floor. It reads 79. What is under the sensor? (a) the white floor (b) the black line
  2. 2.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 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
  3. 3.⬛ The threshold of a light sensor is … (a) the top speed (b) the black/white cut-off (c) the battery size (d) the wheel size
  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 light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  6. 6.⬛ A reading below the threshold means the sensor is over … (a) white (b) the sky (c) black (d) water
  7. 7.🔦 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) the right sensor (b) both sensors (c) the left sensor (d) neither sensor
  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 35. Which sensor is over the black line? (a) both sensors (b) the left sensor (c) the right sensor (d) neither sensor
  9. 9.⬛ Why does a light sensor read a LOW number over a black line? (a) black is hot (b) black is loud (c) black soaks up light (d) black is wet
  10. 10.🔦 A light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  11. 11.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 and the right sensor reads 60. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the left sensor (d) the right sensor
  12. 12.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 46. What is under the sensor? (a) the black line (b) the white floor
  13. 13.🔦 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 black line (b) the white floor
  14. 14.🔦 A light sensor reads 40 over black and 80 over white. A good threshold is halfway between them. What is it?
  15. 15.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 90. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) both sensors (d) the left sensor
  16. 16.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 25. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) the right 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 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 white floor (b) the black line
  19. 19.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 34. What is under the sensor? (a) the white floor (b) the black line
  20. 20.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 76. What is under the sensor? (a) the black line (b) the white floor
  21. 21.🔦 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 black line (b) the white floor
  22. 22.🔦 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 right sensor (b) both sensors (c) the left sensor (d) neither sensor
  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 60. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  24. 24.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 46. What is under the sensor? (a) the black line (b) the white floor
  25. 25.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  26. 26.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 26. 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 62. What is under the sensor? (a) the black line (b) the white floor
  28. 28.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 25. What is under the sensor? (a) the white floor (b) the black line
  29. 29.🔦 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 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 85 and the right sensor reads 90. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the right sensor (d) the left sensor
  31. 31.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 80. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) the right sensor (d) both sensors
  32. 32.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 85 and the right sensor reads 20. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) both sensors (d) the left sensor
  33. 33.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  34. 34.🔦 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 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 34. What is under the sensor? (a) the black line (b) the white floor
  36. 36.🔦 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 black line (b) the white floor
  37. 37.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  38. 38.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 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
  39. 39.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 10. Which sensor is over the black line? (a) neither sensor (b) both sensors (c) the left sensor (d) the right sensor
  40. 40.🔦 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) both sensors (b) the right sensor (c) neither sensor (d) the left sensor

Answer key

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

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