Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 189 · 40 questions

Remember (Measure it, then move it): Match the sensor to the quantity: light, heat, distance, movement, soil wetness, sound, gas or rain. Match the actuator to the action: spin (motor), exact angle (servo), beep (buzzer), light (LED), water (pump), numbers (display). Echo distance = 17 × echo time in ms (cm), because the sound goes there and back.

1. 1.🔍 Which sensor would you use to keep an incubator warm? (a) a soil moisture sensor (b) a motion sensor (c) a light sensor (d) a temperature sensor
2. 2.🔍 Which sensor would you use to close a window in rain? (a) a soil moisture sensor (b) a light sensor (c) a rain sensor (d) a temperature sensor
3. 3.⚙️ Which actuator would you use to show a status light? (a) a buzzer (b) a servo motor (c) an LED (d) a pump
4. 4.Which job needs a soil moisture sensor? (a) spot someone walking in (b) water a dry plant (c) close a window in rain (d) open blinds at sunrise
5. 5.🔍 A distance sensor sends a sound pulse and hears the echo 2 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
6. 6.🔍 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?
7. 7.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) a fuse (c) an output (d) a power source
8. 8.🔍 Which sensor would you use to measure classroom noise? (a) a soil moisture sensor (b) a light sensor (c) a sound sensor (d) a rain sensor
9. 9.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a pump (c) a motor (d) an LED
10. 10.Which job needs a temperature sensor? (a) measure classroom noise (b) close a window in rain (c) switch on with a clap (d) start a fan when hot
11. 11.Which job needs a motion sensor? (a) keep an incubator warm (b) spot someone walking in (c) start a fan when hot (d) open blinds at sunrise
12. 12.🔍 Which sensor would you use to warn of a gas leak? (a) a gas sensor (b) a sound sensor (c) a light sensor (d) a soil moisture sensor
13. 13.Which job needs a motor? (a) show the temperature (b) show a status light (c) open a gate to 90° (d) spin a robot’s wheels
14. 14.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
15. 15.True or false: to measure classroom noise, use a sound sensor. (a) True (b) False
16. 16.🔍 Which sensor would you use to water a dry plant? (a) a motion sensor (b) a soil moisture sensor (c) a gas sensor (d) a sound sensor
17. 17.True or false: to switch on with a clap, use a temperature sensor. (a) False (b) True
18. 18.⚙️ Which actuator would you use to show the temperature? (a) an LED (b) a servo motor (c) a buzzer (d) a display
19. 19.Which job needs a light sensor? (a) make a parking alarm (b) water a dry plant (c) switch on with a clap (d) switch on lamps at dusk
20. 20.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
21. 21.Which job needs a display? (a) move water to plants (b) show a status light (c) beep an alarm (d) show the temperature
22. 22.🔍 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)?
23. 23.Which job needs a servo motor? (a) show the temperature (b) open a gate to 90° (c) show a status light (d) beep an alarm
24. 24.Which job needs a rain sensor? (a) switch on lamps at dusk (b) close a window in rain (c) switch on with a clap (d) keep an incubator warm
25. 25.True or false: to stop a robot near walls, use a sound sensor. (a) True (b) False
26. 26.🔍 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?
27. 27.🔍 An object is 51 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
28. 28.True or false: to warn of a gas leak, use a gas sensor. (a) True (b) False
29. 29.🔍 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)?
30. 30.Which job needs a gas sensor? (a) measure classroom noise (b) water a dry plant (c) warn of a gas leak (d) switch on lamps at dusk
31. 31.🔍 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)?
32. 32.🔍 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?
33. 33.🔍 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)?
34. 34.Which job needs a pump? (a) open a gate to 90° (b) turn to an exact angle (c) move water to plants (d) spin a robot’s wheels
35. 35.🔍 Which sensor would you use to open blinds at sunrise? (a) a light sensor (b) a gas sensor (c) a temperature sensor (d) a soil moisture sensor
36. 36.True or false: to open blinds at sunrise, use a motion sensor. (a) False (b) True
37. 37.True or false: to keep an incubator warm, use a light sensor. (a) False (b) True
38. 38.⚙️ Which actuator would you use to open a gate to 90°? (a) an LED (b) a servo motor (c) a buzzer (d) a motor
39. 39.🔍 Which sensor would you use to make a parking alarm? (a) a gas sensor (b) a sound sensor (c) a soil moisture sensor (d) a distance sensor
40. 40.🔍 Which sensor would you use to start a fan when hot? (a) a distance sensor (b) a motion sensor (c) a temperature sensor (d) a soil moisture sensor

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