DistanceSensor (ultrasonic) in Raspberry Pi - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the DistanceSensor class from gpiozero.

Raspberry Pi

from gpiozero import [1]

Drag options to blanks, or click blank then click option'

ADistanceSensor

BLED

CButton

DMotor

Attempts:

3 left

💡 Hint

Common Mistakes

Importing the wrong class like LED or Button.

Forgetting to import the class.

The DistanceSensor class is imported from the gpiozero library to use the ultrasonic sensor.

2fill in blank

medium

Complete the code to create a DistanceSensor object with trigger pin 17 and echo pin 18.

Raspberry Pi

sensor = DistanceSensor(trigger=[1], echo=18)

Drag options to blanks, or click blank then click option'

A27

B22

C17

D23

Attempts:

3 left

💡 Hint

Common Mistakes

Using the echo pin number for trigger.

Using a wrong pin number.

The trigger pin is set to GPIO 17 as specified.

3fill in blank

hard

Fix the error in the code to print the distance in centimeters.

Raspberry Pi

print(f"Distance: {sensor.[1] * 100:.1f} cm")

Drag options to blanks, or click blank then click option'

Adistance

Bvalue

Cdistance_cm

Ddistance_in

Attempts:

3 left

💡 Hint

Common Mistakes

Using a non-existent property like 'distance_cm'.

Not multiplying by 100 to convert meters to centimeters.

The distance property returns the distance in meters. Multiplying by 100 converts it to centimeters.

4fill in blank

hard

Fill both blanks to create a dictionary of distances for sensors on pins 5 and 6, only if distance is less than 0.5 meters.

Raspberry Pi

distances = {pin: sensor.distance for pin in [5, 6] if sensor.distance [1] [2]

Drag options to blanks, or click blank then click option'

A<

B0.5

C>

D1.0

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' instead of '<'.

Using the wrong threshold value.

The condition checks if the distance is less than 0.5 meters.

5fill in blank

hard

Fill all three blanks to create a dictionary with pin numbers as keys, distances in cm as values, only for distances greater than 0.2 meters.

Raspberry Pi

dist_cm = {pin: sensor.[1] * 100 for pin in [7, 8] if sensor.[2] > [3]

Drag options to blanks, or click blank then click option'

Adistance

C0.2

D0.5

Attempts:

3 left

💡 Hint

Common Mistakes

Using different property names.

Using wrong threshold values.

The dictionary comprehension converts distance to centimeters and filters distances greater than 0.2 meters.