← Light sensors and lines lesson New set →

Robotics Worksheet: Line Follower Light Sensors

Robotics lesson 18: Light sensors and lines · Set 922 · 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 20 over black and 80 over white. A good threshold is halfway between them. What is it?
  2. 2.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 73. What is under the sensor? (a) the white floor (b) the black line
  3. 3.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 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
  4. 4.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 43. What is under the sensor? (a) the white floor (b) the black line
  5. 5.🔦 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
  6. 6.🔦 A light sensor reads 40 over black and 60 over white. A good threshold is halfway between them. What is it?
  7. 7.🔦 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 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 95 and the right sensor reads 15. Which sensor is over the black line? (a) the left sensor (b) both sensors (c) neither sensor (d) the right sensor
  9. 9.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 24. 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 28. What is under the sensor? (a) the white floor (b) the black line
  11. 11.🔦 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
  12. 12.⬛ The threshold of a light sensor is … (a) the battery size (b) the black/white cut-off (c) the top speed (d) the wheel size
  13. 13.🔦 A light sensor reads 20 over black and 70 over white. A good threshold is halfway between them. What is it?
  14. 14.🔦 A light sensor reads 20 over black and 60 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 65 and the right sensor reads 95. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) the left sensor (d) neither sensor
  16. 16.🔦 A light sensor reads 30 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 90 over white. A good threshold is halfway between them. What is it?
  18. 18.🔦 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
  19. 19.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 60 and the right sensor reads 75. Which sensor is over the black line? (a) the left sensor (b) neither sensor (c) the right sensor (d) both sensors
  20. 20.🔦 A light sensor reads 30 over black and 80 over white. A good threshold is halfway between them. What is it?
  21. 21.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 95 and the right sensor reads 35. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) the left sensor (d) both sensors
  22. 22.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 48. What is under the sensor? (a) the black line (b) the white floor
  23. 23.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 85 and the right sensor reads 95. Which sensor is over the black line? (a) the right sensor (b) both sensors (c) the left sensor (d) neither sensor
  24. 24.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 52. What is under the sensor? (a) the black line (b) the white floor
  25. 25.🔦 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 white floor (b) the black line
  26. 26.🔦 A light sensor reads 40 over black and 70 over white. A good threshold is halfway between them. What is it?
  27. 27.🔦 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) the right sensor (b) the left sensor (c) neither sensor (d) both sensors
  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 25. Which sensor is over the black line? (a) both sensors (b) neither sensor (c) the right sensor (d) the left sensor
  29. 29.🔦 A light sensor reads 10 over black and 90 over white. A good threshold is halfway between them. What is it?
  30. 30.⬛ In a two-sensor line follower, both sensors see white. Where is the line? (a) under the right sensor (b) between the two sensors (c) far behind it (d) under the left sensor
  31. 31.🔦 A robot has a left and a right light sensor. Below 50 means black. The left sensor reads 20 and the right sensor reads 95. Which sensor is over the black line? (a) neither sensor (b) the right sensor (c) the left sensor (d) both sensors
  32. 32.⬛ Why does a light sensor read a LOW number over a black line? (a) black soaks up light (b) black is hot (c) black is wet (d) black is loud
  33. 33.🔦 A light sensor reads 10 over black and 80 over white. A good threshold is halfway between them. What is it?
  34. 34.🔦 A light sensor reads 40 over black and 90 over white. A good threshold is halfway between them. What is it?
  35. 35.🔦 A light sensor reads 10 over black and 60 over white. A good threshold is halfway between them. What is it?
  36. 36.🔦 A light sensor reads below 30 over a black line and above 30 over the white floor. It reads 20. What is under the sensor? (a) the black line (b) the white floor
  37. 37.🔦 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 black line (b) the white floor
  38. 38.🔦 A light sensor reads below 60 over a black line and above 60 over the white floor. It reads 65. What is under the sensor? (a) the black line (b) the white floor
  39. 39.🔦 A light sensor reads below 50 over a black line and above 50 over the white floor. It reads 30. What is under the sensor? (a) the black line (b) the white floor
  40. 40.🔦 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

Answer key

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

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