Electronics Worksheet: Sensors and Actuators

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

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