Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 323 · 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.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
2. 2.Which job needs a motion sensor? (a) keep an incubator warm (b) close a window in rain (c) spot someone walking in (d) switch on lamps at dusk
3. 3.Which job needs a temperature sensor? (a) open blinds at sunrise (b) measure classroom noise (c) make a parking alarm (d) start a fan when hot
4. 4.Which job needs a rain sensor? (a) close a window in rain (b) open blinds at sunrise (c) stop a robot near walls (d) make a parking alarm
5. 5.🔍 Which sensor would you use to warn of a gas leak? (a) a rain sensor (b) a distance sensor (c) a light sensor (d) a gas sensor
6. 6.Which job needs an LED? (a) move water to plants (b) show a status light (c) beep an alarm (d) show the temperature
7. 7.⚙️ Which actuator would you use to show the temperature? (a) a buzzer (b) a display (c) a pump (d) an LED
8. 8.🔍 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?
9. 9.🔍 A distance sensor sends a sound pulse and hears the echo 17 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
10. 10.🔍 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?
11. 11.True or false: to start a fan when hot, use a motion sensor. (a) True (b) False
12. 12.Which job needs a buzzer? (a) show a status light (b) turn to an exact angle (c) spin a robot’s wheels (d) beep an alarm
13. 13.Which job needs a soil moisture sensor? (a) switch on with a clap (b) make a parking alarm (c) water a dry plant (d) close a window in rain
14. 14.Which job needs a servo motor? (a) beep an alarm (b) move water to plants (c) spin a robot’s wheels (d) turn to an exact angle
15. 15.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
16. 16.🔍 Which sensor would you use to water a dry plant? (a) a light sensor (b) a distance sensor (c) a soil moisture sensor (d) a rain sensor
17. 17.⚙️ Which actuator would you use to show a status light? (a) a buzzer (b) an LED (c) a motor (d) a display
18. 18.🔍 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)?
19. 19.🔍 A distance sensor sends a sound pulse and hears the echo 3 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
20. 20.🔍 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)?
21. 21.Which job needs a light sensor? (a) start a fan when hot (b) measure classroom noise (c) spot someone walking in (d) open blinds at sunrise
22. 22.Which job needs a servo motor? (a) beep an alarm (b) open a gate to 90° (c) spin a robot’s wheels (d) move water to plants
23. 23.🔍 Which sensor would you use to switch on with a clap? (a) a sound sensor (b) a soil moisture sensor (c) a temperature sensor (d) a distance sensor
24. 24.🔍 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)?
25. 25.True or false: to keep an incubator warm, use a soil moisture sensor. (a) True (b) False
26. 26.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a motor (b) a display (c) an LED (d) a buzzer
27. 27.Which job needs a motor? (a) show the temperature (b) spin a robot’s wheels (c) show a status light (d) beep an alarm
28. 28.Which job needs a display? (a) show a status light (b) open a gate to 90° (c) spin a robot’s wheels (d) show the temperature
29. 29.🔍 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)?
30. 30.🔍 Which sensor would you use to keep an incubator warm? (a) a temperature sensor (b) a soil moisture sensor (c) a rain sensor (d) a sound sensor
31. 31.⚙️ Which actuator would you use to turn to an exact angle? (a) a pump (b) a servo motor (c) an LED (d) a buzzer
32. 32.🔍 An object is 238 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
33. 33.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an output (d) an input
34. 34.Which job needs a gas sensor? (a) start a fan when hot (b) open blinds at sunrise (c) keep an incubator warm (d) warn of a gas leak
35. 35.True or false: to warn of a gas leak, use a motion sensor. (a) True (b) False
36. 36.🔍 A distance sensor sends a sound pulse and hears the echo 14 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
37. 37.True or false: to switch on lamps at dusk, use a gas sensor. (a) True (b) False
38. 38.🔍 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?
39. 39.True or false: to switch on lamps at dusk, use a rain sensor. (a) False (b) True
40. 40.⚙️ Which actuator would you use to open a gate to 90°? (a) a display (b) a motor (c) a servo motor (d) a pump

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