Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 110 · 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 spot someone walking in, use a soil moisture sensor. (a) False (b) True
2. 2.Which job needs a soil moisture sensor? (a) water a dry plant (b) warn of a gas leak (c) stop a robot near walls (d) open blinds at sunrise
3. 3.Which job needs a motor? (a) open a gate to 90° (b) move water to plants (c) show a status light (d) spin a robot’s wheels
4. 4.Which job needs a distance sensor? (a) start a fan when hot (b) make a parking alarm (c) keep an incubator warm (d) warn of a gas leak
5. 5.⚙️ What is an actuator? (a) a battery (b) a sensor (c) a program (d) an output that acts
6. 6.Which job needs a motion sensor? (a) open blinds at sunrise (b) close a window in rain (c) warn of a gas leak (d) spot someone walking in
7. 7.🔍 Which sensor would you use to open blinds at sunrise? (a) a light sensor (b) a motion sensor (c) a gas sensor (d) a distance sensor
8. 8.Which job needs a servo motor? (a) spin a robot’s wheels (b) show a status light (c) show the temperature (d) turn to an exact angle
9. 9.🔍 Which sensor would you use to warn of a gas leak? (a) a distance sensor (b) a soil moisture sensor (c) a gas sensor (d) a motion sensor
10. 10.True or false: to water a dry plant, use a rain sensor. (a) False (b) True
11. 11.🔍 Which sensor would you use to make a parking alarm? (a) a distance sensor (b) a temperature sensor (c) a light sensor (d) a gas sensor
12. 12.Which job needs a pump? (a) open a gate to 90° (b) show the temperature (c) move water to plants (d) turn to an exact angle
13. 13.True or false: to open blinds at sunrise, use a motion sensor. (a) False (b) True
14. 14.⚙️ Which actuator would you use to beep an alarm? (a) a pump (b) a servo motor (c) a buzzer (d) an LED
15. 15.Which job needs a display? (a) open a gate to 90° (b) show the temperature (c) spin a robot’s wheels (d) show a status light
16. 16.🔍 An object is 272 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
17. 17.Which job needs a light sensor? (a) warn of a gas leak (b) spot someone walking in (c) close a window in rain (d) open blinds at sunrise
18. 18.Which job needs a temperature sensor? (a) keep an incubator warm (b) switch on with a clap (c) switch on lamps at dusk (d) water a dry plant
19. 19.Which job needs a distance sensor? (a) keep an incubator warm (b) spot someone walking in (c) switch on lamps at dusk (d) stop a robot near walls
20. 20.🔍 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?
21. 21.True or false: to keep an incubator warm, use a soil moisture sensor. (a) False (b) True
22. 22.🔍 Which sensor would you use to spot someone walking in? (a) a gas sensor (b) a distance sensor (c) a motion sensor (d) a rain sensor
23. 23.Which job needs a servo motor? (a) move water to plants (b) open a gate to 90° (c) show the temperature (d) spin a robot’s wheels
24. 24.True or false: to make a parking alarm, use a temperature sensor. (a) True (b) False
25. 25.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
26. 26.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a display (b) a buzzer (c) a servo motor (d) a motor
27. 27.🔍 Which sensor would you use to start a fan when hot? (a) a distance sensor (b) a gas sensor (c) a light sensor (d) a temperature sensor
28. 28.Which job needs an LED? (a) spin a robot’s wheels (b) open a gate to 90° (c) show a status light (d) beep an alarm
29. 29.🔍 Which sensor would you use to water a dry plant? (a) a gas sensor (b) a temperature sensor (c) a soil moisture sensor (d) a light sensor
30. 30.🔍 Which sensor would you use to close a window in rain? (a) a distance sensor (b) a rain sensor (c) a motion sensor (d) a temperature sensor
31. 31.True or false: to make a parking alarm, use a distance sensor. (a) True (b) False
32. 32.🔍 A distance sensor sends a sound pulse and hears the echo 9 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
33. 33.🔍 Which sensor would you use to switch on lamps at dusk? (a) a light sensor (b) a temperature sensor (c) a motion sensor (d) a sound sensor
34. 34.Which job needs a buzzer? (a) beep an alarm (b) show the temperature (c) spin a robot’s wheels (d) open a gate to 90°
35. 35.🔍 Which sensor would you use to switch on with a clap? (a) a sound sensor (b) a light sensor (c) a soil moisture sensor (d) a distance sensor
36. 36.🔍 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)?
37. 37.True or false: to warn of a gas leak, use a light sensor. (a) False (b) True
38. 38.True or false: to switch on lamps at dusk, use a distance sensor. (a) True (b) False
39. 39.⚙️ Which actuator would you use to show the temperature? (a) a motor (b) a display (c) a buzzer (d) a servo motor
40. 40.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a light sensor (c) a gas sensor (d) a sound sensor

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