← Light sensors and lines lesson New set →

Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 463 · 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 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  2. 2.⬛ Why does a light sensor read a LOW number over a black line? (a) black is loud (b) black is wet (c) black is hot (d) black soaks up light
  3. 3.🔦 A light sensor reads 20 over black and 80 over white. A good threshold is halfway between them. What is it?
  4. 4.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 70 and the right sensor reads 15. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) the right sensor (d) neither sensor
  5. 5.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 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
  6. 6.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 26. What is under the sensor? (a) the white floor (b) the black line
  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 80 over white. A good threshold is halfway between them. What is it?
  9. 9.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 40 and the right sensor reads 25. Which sensor is over the black line? (a) the right sensor (b) the left sensor (c) neither sensor (d) both sensors
  10. 10.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  11. 11.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 53. What is under the sensor? (a) the white floor (b) the black line
  12. 12.🔦 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
  13. 13.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 25 and the right sensor reads 35. Which sensor is over the black line? (a) the right sensor (b) neither sensor (c) both sensors (d) the left sensor
  14. 14.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) far behind it (b) under the right sensor (c) under the left sensor (d) between the two sensors
  15. 15.🔦 A light sensor reads 20 over black and 60 over white. A good threshold is halfway between them. What is it?
  16. 16.🔦 A light sensor reads 40 over black and 80 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 23. What is under the sensor? (a) the black line (b) the white floor
  18. 18.🔦 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) the right sensor (c) the left sensor (d) both sensors
  19. 19.⬛ A reading below the threshold means the sensor is over … (a) white (b) the sky (c) water (d) black
  20. 20.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 43. What is under the sensor? (a) the black line (b) the white floor
  21. 21.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 80. What is under the sensor? (a) the black line (b) the white floor
  22. 22.🔦 A light sensor reads 10 over black and 70 over white. A good threshold is halfway between them. What is it?
  23. 23.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 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 60 over a black line and above 60 over the white floor. It reads 37. What is under the sensor? (a) the white floor (b) the black line
  25. 25.🔦 A light sensor reads below 40 over a black line and above 40 over the white floor. It reads 57. What is under the sensor? (a) the black line (b) the white floor
  26. 26.🔦 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 right sensor (b) neither sensor (c) both sensors (d) the left sensor
  27. 27.🔦 A light sensor reads 30 over black and 90 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 40 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
  29. 29.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 10 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
  30. 30.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 80 and the right sensor reads 65. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the right sensor (d) the left sensor
  31. 31.🔦 A light sensor reads 30 over black and 60 over white. A good threshold is halfway between them. What is it?
  32. 32.⬛ The threshold of a light sensor is … (a) the black/white cut-off (b) the wheel size (c) the battery size (d) the top speed
  33. 33.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 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
  34. 34.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 44. What is under the sensor? (a) the white floor (b) the black line
  35. 35.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 95. Which sensor is over the black line? (a) neither sensor (b) the left sensor (c) both sensors (d) the right sensor
  36. 36.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 15 and the right sensor reads 15. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  37. 37.🔦 A light sensor reads 30 over black and 70 over white. A good threshold is halfway between them. What is it?
  38. 38.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 64. What is under the sensor? (a) the white floor (b) the black line
  39. 39.🔦 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
  40. 40.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?

Answer key

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

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