Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 215 · 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 water a dry plant? (a) a rain sensor (b) a soil moisture sensor (c) a light sensor (d) a motion sensor
2. 2.🔍 An object is 306 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
3. 3.🔍 Which sensor would you use to close a window in rain? (a) a motion sensor (b) a sound sensor (c) a rain sensor (d) a soil moisture sensor
4. 4.Which job needs an LED? (a) open a gate to 90° (b) spin a robot’s wheels (c) beep an alarm (d) show a status light
5. 5.Which job needs a temperature sensor? (a) water a dry plant (b) switch on lamps at dusk (c) keep an incubator warm (d) open blinds at sunrise
6. 6.True or false: to open blinds at sunrise, use a distance sensor. (a) True (b) False
7. 7.⚙️ Which actuator would you use to open a gate to 90°? (a) a display (b) a buzzer (c) a motor (d) a servo motor
8. 8.Which job needs a sound sensor? (a) keep an incubator warm (b) stop a robot near walls (c) warn of a gas leak (d) measure classroom noise
9. 9.True or false: to keep an incubator warm, use a temperature sensor. (a) True (b) False
10. 10.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
11. 11.🔍 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)?
12. 12.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a pump (b) a buzzer (c) an LED (d) a motor
13. 13.🔍 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?
14. 14.🔍 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)?
15. 15.Which job needs a display? (a) show a status light (b) show the temperature (c) spin a robot’s wheels (d) beep an alarm
16. 16.Which job needs a motion sensor? (a) keep an incubator warm (b) water a dry plant (c) spot someone walking in (d) switch on lamps at dusk
17. 17.True or false: to stop a robot near walls, use a rain sensor. (a) True (b) False
18. 18.Which job needs a servo motor? (a) show the temperature (b) open a gate to 90° (c) beep an alarm (d) show a status light
19. 19.🔍 Which sensor would you use to keep an incubator warm? (a) a gas sensor (b) a soil moisture sensor (c) a temperature sensor (d) a light sensor
20. 20.⚙️ What is an actuator? (a) an output that acts (b) a program (c) a sensor (d) a battery
21. 21.🔍 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)?
22. 22.🔍 Which sensor would you use to measure classroom noise? (a) a gas sensor (b) a light sensor (c) a temperature sensor (d) a sound sensor
23. 23.🔍 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)?
24. 24.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an input (c) an output (d) a fuse
25. 25.🔍 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)?
26. 26.🔍 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?
27. 27.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
28. 28.Which job needs a soil moisture sensor? (a) switch on with a clap (b) start a fan when hot (c) measure classroom noise (d) water a dry plant
29. 29.True or false: to make a parking alarm, use a light sensor. (a) True (b) False
30. 30.🔍 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?
31. 31.⚙️ Which actuator would you use to beep an alarm? (a) an LED (b) a servo motor (c) a display (d) a buzzer
32. 32.Which job needs a gas sensor? (a) close a window in rain (b) water a dry plant (c) warn of a gas leak (d) switch on with a clap
33. 33.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
34. 34.🔍 Which sensor would you use to spot someone walking in? (a) a sound sensor (b) a motion sensor (c) a rain sensor (d) a distance sensor
35. 35.🔍 Which sensor would you use to switch on lamps at dusk? (a) a soil moisture sensor (b) a temperature sensor (c) a light sensor (d) a motion sensor
36. 36.🔍 Which sensor would you use to make a parking alarm? (a) a sound sensor (b) a motion sensor (c) a soil moisture sensor (d) a distance sensor
37. 37.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a motor (c) a servo motor (d) a buzzer
38. 38.Which job needs a buzzer? (a) open a gate to 90° (b) spin a robot’s wheels (c) turn to an exact angle (d) beep an alarm
39. 39.Which job needs a light sensor? (a) close a window in rain (b) keep an incubator warm (c) water a dry plant (d) open blinds at sunrise
40. 40.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True

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