← Light sensors and lines lesson New set →

Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 99 · 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 reading below the threshold means the sensor is over … (a) water (b) white (c) black (d) the sky
  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 60 over white. A good threshold is halfway between them. What is it?
  4. 4.⬛ The threshold of a light sensor is … (a) the black/white cut-off (b) the battery size (c) the top speed (d) the wheel size
  5. 5.🔦 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
  6. 6.🔦 A light sensor reads 20 over black and 90 over white. A good threshold is halfway between them. What is it?
  7. 7.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  8. 8.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  9. 9.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 33. What is under the sensor? (a) the black line (b) the white floor
  10. 10.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 31. What is under the sensor? (a) the black line (b) the white floor
  11. 11.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 and the right sensor reads 65. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  12. 12.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 35 and the right sensor reads 95. Which sensor is over the black line? (a) the left sensor (b) the right sensor (c) neither sensor (d) both sensors
  13. 13.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 21. What is under the sensor? (a) the white floor (b) the black line
  14. 14.⬛ Why does a light sensor read a LOW number over a black line? (a) black is hot (b) black is wet (c) black soaks up light (d) black is loud
  15. 15.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 27. What is under the sensor? (a) the white floor (b) the black line
  16. 16.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 50. What is under the sensor? (a) the black line (b) the white floor
  17. 17.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 70. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) both sensors (d) the right sensor
  18. 18.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) far behind it (b) under the left sensor (c) between the two sensors (d) under the right sensor
  19. 19.🔦 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 black line (b) the white floor
  20. 20.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 85. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) neither sensor (d) the left sensor
  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 robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 10. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) both sensors (d) the left sensor
  23. 23.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  24. 24.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  25. 25.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  26. 26.🔦 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
  27. 27.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  28. 28.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 30. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) the right sensor (d) both sensors
  29. 29.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 30 and the right sensor reads 25. Which sensor is over the black line? (a) both sensors (b) the right sensor (c) neither sensor (d) the left sensor
  30. 30.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  31. 31.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 30 and the right sensor reads 85. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) both sensors (d) the left sensor
  32. 32.🔦 A light sensor reads 30 over black and 90 over white. A good threshold is halfway between them. What is it?
  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 90. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  34. 34.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 59. 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 17. 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 70 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
  37. 37.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 90 and the right sensor reads 65. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) the left sensor (d) both sensors
  38. 38.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 30 and the right sensor reads 80. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  39. 39.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 33. What is under the sensor? (a) the black line (b) the white floor
  40. 40.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 35. What is under the sensor? (a) the black line (b) the white floor

Answer key

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

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