Robotics Worksheet: Ultrasonic Distance Sensor

Robotics lesson 17: The distance sensor · Set 464 · 40 questions

Robot tip (Half the echo path): Distance (cm) = 17 × echo time (ms), because 34 cm per ms ÷ 2 for there and back. Echo time (ms) = distance × 2 ÷ 34. Distance after driving = distance now − speed × time.

1. 1.📡 An object is 34 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
2. 2.📡 An object is 272 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
3. 3.📡 An object is 323 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
4. 4.📡 A distance sensor sends a sound pulse and hears the echo 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
5. 5.📡 A robot stops if an object is closer than 50 cm. Its distance sensor hears the echo after 7 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
6. 6.📡 An object is 68 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
7. 7.📡 A robot stops if an object is closer than 30 cm. Its distance sensor hears the echo after 2 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
8. 8.📡 A distance sensor sends a sound pulse and hears the echo 4 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
9. 9.📡 Which object is hardest for an echo sensor to notice? (a) a flat wall (b) a metal door (c) a soft foam cushion (d) a wooden box
10. 10.📡 A robot stops if an object is closer than 50 cm. Its distance sensor hears the echo after 2 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
11. 11.📡 A robot stops if an object is closer than 30 cm. Its distance sensor hears the echo after 5 ms (sound: about 34 cm per ms). Does the robot stop? (a) No (b) Yes
12. 12.📡 A robot is 160 cm from a wall and drives straight at it at 5 cm per second. How far from the wall is it after 22 seconds (in cm)?
13. 13.📡 A robot stops if an object is closer than 30 cm. Its distance sensor hears the echo after 1 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
14. 14.📡 A distance sensor sends a sound pulse and hears the echo 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
15. 15.📡 A robot is 200 cm from a wall and drives straight at it at 15 cm per second. How far from the wall is it after 6 seconds (in cm)?
16. 16.📡 An object is 85 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
17. 17.📡 An object is 221 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
18. 18.📡 A distance sensor sends a sound pulse and hears the echo 6 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
19. 19.📡 An object is 306 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
20. 20.📡 A distance sensor sends a sound pulse and hears the echo 16 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
21. 21.📡 A distance sensor sends a sound pulse and hears the echo 1 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
22. 22.📡 An object is 153 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
23. 23.📡 A distance sensor sends a sound pulse and hears the echo 13 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
24. 24.📡 Why do we halve the echo’s total path? (a) to make it smaller (b) sound is slow (c) it goes there and back (d) the sensor is half
25. 25.📡 A robot is 120 cm from a wall and drives straight at it at 20 cm per second. How far from the wall is it after 1 second (in cm)?
26. 26.📡 Which animal finds its way by echoes, like this sensor? (a) a goldfish (b) a snail (c) a cow (d) a bat
27. 27.📡 A robot is 210 cm from a wall and drives straight at it at 15 cm per second. How far from the wall is it after 13 seconds (in cm)?
28. 28.📡 What does an ultrasonic distance sensor send out? (a) sound too high to hear (b) water drops (c) bright light (d) radio music
29. 29.📡 A robot is 100 cm from a wall and drives straight at it at 20 cm per second. How far from the wall is it after 4 seconds (in cm)?
30. 30.📡 A robot stops if an object is closer than 100 cm. Its distance sensor hears the echo after 5 ms (sound: about 34 cm per ms). Does the robot stop? (a) No (b) Yes
31. 31.📡 A robot stops if an object is closer than 30 cm. Its distance sensor hears the echo after 3 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
32. 32.📡 A robot is 200 cm from a wall and drives straight at it at 20 cm per second. How far from the wall is it after 6 seconds (in cm)?
33. 33.📡 A distance sensor sends a sound pulse and hears the echo 8 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
34. 34.📡 A robot is 120 cm from a wall and drives straight at it at 10 cm per second. How far from the wall is it after 1 second (in cm)?
35. 35.📡 An object is 255 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
36. 36.📡 In these lessons, sound travels about how far in 1 millisecond? (a) 1 km (b) 34 cm (c) 340 cm (d) 3 cm
37. 37.📡 A robot is 140 cm from a wall and drives straight at it at 10 cm per second. How far from the wall is it after 8 seconds (in cm)?
38. 38.📡 A robot is 110 cm from a wall and drives straight at it at 10 cm per second. How far from the wall is it after 4 seconds (in cm)?
39. 39.📡 A robot stops if an object is closer than 100 cm. Its distance sensor hears the echo after 2 ms (sound: about 34 cm per ms). Does the robot stop? (a) No (b) Yes
40. 40.📡 A distance sensor sends a sound pulse and hears the echo 12 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?

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