← Light sensors and lines lesson New set →

Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 141 · 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 robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 60. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  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 light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  4. 4.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 46. What is under the sensor? (a) the white floor (b) the black line
  5. 5.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  6. 6.🔦 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 white floor (b) the black line
  7. 7.🔦 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
  8. 8.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 17. What is under the sensor? (a) the white floor (b) the black line
  9. 9.🔦 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 black line (b) the white floor
  10. 10.🔦 A light sensor reads 40 over black and 70 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 75 and the right sensor reads 65. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) both sensors (d) neither sensor
  12. 12.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 10. What is under the sensor? (a) the white floor (b) the black line
  13. 13.🔦 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
  14. 14.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 85 and the right sensor reads 85. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) both sensors (d) the right sensor
  15. 15.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  16. 16.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  17. 17.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  18. 18.⬛ 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) far behind it (d) between the two sensors
  19. 19.⬛ A reading below the threshold means the sensor is over … (a) water (b) white (c) black (d) the sky
  20. 20.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 60. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) the left sensor (d) neither sensor
  21. 21.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 85. What is under the sensor? (a) the black line (b) the white floor
  22. 22.🔦 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 black line (b) the white floor
  23. 23.🔦 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
  24. 24.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 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
  25. 25.🔦 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
  26. 26.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 60. What is under the sensor? (a) the white floor (b) the black line
  27. 27.⬛ Why does a light sensor read a LOW number over a black line? (a) black is loud (b) black soaks up light (c) black is hot (d) black is wet
  28. 28.🔦 A light sensor reads 20 over black and 80 over white. A good threshold is halfway between them. What is it?
  29. 29.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  30. 30.🔦 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) both sensors (b) the left sensor (c) the right sensor (d) neither sensor
  31. 31.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 28. 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 60 and the right sensor reads 40. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  33. 33.🔦 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 white floor (b) the black line
  34. 34.⬛ The threshold of a light sensor is … (a) the wheel size (b) the black/white cut-off (c) the battery size (d) the top speed
  35. 35.🔦 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) both sensors (b) the left sensor (c) the right sensor (d) neither sensor
  36. 36.🔦 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) both sensors (b) the left sensor (c) neither sensor (d) the right sensor
  37. 37.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 54. What is under the sensor? (a) the white floor (b) the black line
  38. 38.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 17. What is under the sensor? (a) the white floor (b) the black line
  39. 39.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 62. What is under the sensor? (a) the white floor (b) the black line
  40. 40.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 69. What is under the sensor? (a) the black line (b) the white floor

Answer key

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

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