Robotics Worksheet: Ultrasonic Distance Sensor
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.
NameDateTime takenScore ___ / 40
- 1.📡 What does an ultrasonic distance sensor send out? (a) radio music (b) bright light (c) water drops (d) sound too high to hear
- 2.📡 An object is 136 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 3.📡 An object is 204 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 4.📡 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?
- 5.📡 A distance sensor sends a sound pulse and hears the echo 18 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
- 6.📡 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)?
- 7.📡 Why do we halve the echo’s total path? (a) to make it smaller (b) the sensor is half (c) it goes there and back (d) sound is slow
- 8.📡 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)?
- 9.📡 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?
- 10.📡 A robot is 300 cm from a wall and drives straight at it at 20 cm per second. How far from the wall is it after 7 seconds (in cm)?
- 11.📡 A robot is 150 cm from a wall and drives straight at it at 5 cm per second. How far from the wall is it after 3 seconds (in cm)?
- 12.📡 A robot is 220 cm from a wall and drives straight at it at 15 cm per second. How far from the wall is it after 8 seconds (in cm)?
- 13.📡 An object is 289 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 14.📡 An object is 102 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 15.📡 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)?
- 16.📡 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 8 seconds (in cm)?
- 17.📡 A robot stops if an object is closer than 100 cm. Its distance sensor hears the echo after 7 ms (sound: about 34 cm per ms). Does the robot stop? (a) No (b) Yes
- 18.📡 A robot is 190 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)?
- 19.📡 A distance sensor sends a sound pulse and hears the echo 15 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
- 20.📡 An object is 187 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 21.📡 Which animal finds its way by echoes, like this sensor? (a) a goldfish (b) a snail (c) a bat (d) a cow
- 22.📡 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
- 23.📡 In these lessons, sound travels about how far in 1 millisecond? (a) 34 cm (b) 1 km (c) 340 cm (d) 3 cm
- 24.📡 A robot is 110 cm from a wall and drives straight at it at 5 cm per second. How far from the wall is it after 8 seconds (in cm)?
- 25.📡 A robot is 280 cm from a wall and drives straight at it at 5 cm per second. How far from the wall is it after 23 seconds (in cm)?
- 26.📡 An object is 119 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 27.📡 A distance sensor sends a sound pulse and hears the echo 20 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
- 28.📡 A robot stops if an object is closer than 60 cm. Its distance sensor hears the echo after 5 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
- 29.📡 A distance sensor sends a sound pulse and hears the echo 10 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
- 30.📡 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)?
- 31.📡 An object is 340 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 32.📡 A robot is 220 cm from a wall and drives straight at it at 10 cm per second. How far from the wall is it after 11 seconds (in cm)?
- 33.📡 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?
- 34.📡 An object is 17 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
- 35.📡 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)?
- 36.📡 A robot is 150 cm from a wall and drives straight at it at 5 cm per second. How far from the wall is it after 11 seconds (in cm)?
- 37.📡 A robot stops if an object is closer than 50 cm. Its distance sensor hears the echo after 1 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
- 38.📡 A robot stops if an object is closer than 30 cm. Its distance sensor hears the echo after 4 ms (sound: about 34 cm per ms). Does the robot stop? (a) Yes (b) No
- 39.📡 A robot is 250 cm from a wall and drives straight at it at 15 cm per second. How far from the wall is it after 16 seconds (in cm)?
- 40.📡 A robot is 280 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)?
Answer key
- sound too high to hear
- 8
- 12
- 18
- 306
- 17
- it goes there and back
- 323
- 13
- 160
- 135
- 100
- 17
- 6
- 68
- 40
- No
- 70
- 255
- 11
- a bat
- No
- 34 cm
- 70
- 165
- 7
- 340
- No
- 170
- 272
- 20
- 110
- 5
- 1
- 102
- 95
- Yes
- No
- 10
- 160
Free robotics lessons, practice and worksheets at talentjr.in/robotics-for-kids