Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 43 · 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 spot someone walking in? (a) a distance sensor (b) a temperature sensor (c) a motion sensor (d) a gas sensor
2. 2.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
3. 3.True or false: to water a dry plant, use a light sensor. (a) False (b) True
4. 4.Which job needs a motion sensor? (a) switch on lamps at dusk (b) spot someone walking in (c) make a parking alarm (d) warn of a gas leak
5. 5.Which job needs a sound sensor? (a) make a parking alarm (b) switch on with a clap (c) switch on lamps at dusk (d) close a window in rain
6. 6.🔍 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?
7. 7.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a servo motor (c) a buzzer (d) an LED
8. 8.True or false: to close a window in rain, use a rain sensor. (a) True (b) False
9. 9.⚙️ Which actuator would you use to open a gate to 90°? (a) a buzzer (b) a motor (c) an LED (d) a servo motor
10. 10.Which job needs a soil moisture sensor? (a) water a dry plant (b) open blinds at sunrise (c) warn of a gas leak (d) close a window in rain
11. 11.Which job needs a pump? (a) show a status light (b) move water to plants (c) turn to an exact angle (d) open a gate to 90°
12. 12.Which job needs a distance sensor? (a) warn of a gas leak (b) measure classroom noise (c) stop a robot near walls (d) switch on lamps at dusk
13. 13.🔍 Which sensor would you use to open blinds at sunrise? (a) a light sensor (b) a distance sensor (c) a soil moisture sensor (d) a gas sensor
14. 14.🔍 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?
15. 15.Which job needs an LED? (a) beep an alarm (b) show the temperature (c) show a status light (d) move water to plants
16. 16.🔍 Which sensor would you use to keep an incubator warm? (a) a light sensor (b) a temperature sensor (c) a rain sensor (d) a distance sensor
17. 17.True or false: to make a parking alarm, use a motion sensor. (a) True (b) False
18. 18.Which job needs a servo motor? (a) show the temperature (b) move water to plants (c) spin a robot’s wheels (d) open a gate to 90°
19. 19.Which job needs a gas sensor? (a) warn of a gas leak (b) switch on lamps at dusk (c) keep an incubator warm (d) start a fan when hot
20. 20.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a fuse (c) an input (d) a power source
21. 21.True or false: to open blinds at sunrise, use a motion sensor. (a) False (b) True
22. 22.Which job needs a distance sensor? (a) switch on lamps at dusk (b) make a parking alarm (c) spot someone walking in (d) measure classroom noise
23. 23.🔍 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)?
24. 24.🔍 Which sensor would you use to start a fan when hot? (a) a gas sensor (b) a temperature sensor (c) a distance sensor (d) a light sensor
25. 25.⚙️ Which actuator would you use to show a status light? (a) a pump (b) an LED (c) a motor (d) a display
26. 26.⚙️ Which actuator would you use to turn to an exact angle? (a) an LED (b) a pump (c) a buzzer (d) a servo motor
27. 27.🔍 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?
28. 28.True or false: to keep an incubator warm, use a temperature sensor. (a) False (b) True
29. 29.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
30. 30.🔍 Which sensor would you use to switch on with a clap? (a) a sound sensor (b) a gas sensor (c) a distance sensor (d) a temperature sensor
31. 31.Which job needs a servo motor? (a) move water to plants (b) turn to an exact angle (c) show the temperature (d) spin a robot’s wheels
32. 32.Which job needs a temperature sensor? (a) warn of a gas leak (b) keep an incubator warm (c) close a window in rain (d) switch on lamps at dusk
33. 33.Which job needs a buzzer? (a) spin a robot’s wheels (b) beep an alarm (c) open a gate to 90° (d) show a status light
34. 34.🔍 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)?
35. 35.True or false: to switch on with a clap, use a light sensor. (a) False (b) True
36. 36.🔍 An object is 170 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
37. 37.⚙️ What is an actuator? (a) a battery (b) a program (c) a sensor (d) an output that acts
38. 38.True or false: to stop a robot near walls, use a temperature sensor. (a) False (b) True
39. 39.🔍 Which sensor would you use to warn of a gas leak? (a) a light sensor (b) a soil moisture sensor (c) a gas sensor (d) a rain sensor
40. 40.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a display (c) an LED (d) a pump

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