Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 251 · 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 job needs a distance sensor? (a) open blinds at sunrise (b) switch on lamps at dusk (c) start a fan when hot (d) stop a robot near walls
2. 2.🔍 Which sensor would you use to warn of a gas leak? (a) a gas sensor (b) a temperature sensor (c) a distance sensor (d) a sound sensor
3. 3.Which job needs a servo motor? (a) show a status light (b) move water to plants (c) turn to an exact angle (d) spin a robot’s wheels
4. 4.🔍 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?
5. 5.🔍 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)?
6. 6.🔍 Which sensor would you use to close a window in rain? (a) a soil moisture sensor (b) a rain sensor (c) a gas sensor (d) a motion sensor
7. 7.🔍 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?
8. 8.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
9. 9.Which job needs a soil moisture sensor? (a) measure classroom noise (b) switch on lamps at dusk (c) water a dry plant (d) warn of a gas leak
10. 10.🔍 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)?
11. 11.Which job needs a temperature sensor? (a) switch on with a clap (b) water a dry plant (c) switch on lamps at dusk (d) start a fan when hot
12. 12.🔍 Which sensor would you use to stop a robot near walls? (a) a temperature sensor (b) a motion sensor (c) a distance sensor (d) a sound sensor
13. 13.True or false: to make a parking alarm, use a light sensor. (a) True (b) False
14. 14.Which job needs an LED? (a) turn to an exact angle (b) show a status light (c) show the temperature (d) move water to plants
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.True or false: to open blinds at sunrise, use a rain sensor. (a) True (b) False
17. 17.Which job needs a distance sensor? (a) measure classroom noise (b) water a dry plant (c) start a fan when hot (d) make a parking alarm
18. 18.True or false: to spot someone walking in, use a light sensor. (a) False (b) True
19. 19.🔍 Which sensor would you use to switch on lamps at dusk? (a) a gas sensor (b) a sound sensor (c) a light sensor (d) a rain sensor
20. 20.Which job needs a display? (a) beep an alarm (b) open a gate to 90° (c) show the temperature (d) show a status light
21. 21.🔍 An object is 221 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
22. 22.🔍 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)?
23. 23.Which job needs a rain sensor? (a) close a window in rain (b) water a dry plant (c) keep an incubator warm (d) spot someone walking in
24. 24.Which job needs a gas sensor? (a) spot someone walking in (b) warn of a gas leak (c) measure classroom noise (d) start a fan when hot
25. 25.Which job needs a pump? (a) turn to an exact angle (b) open a gate to 90° (c) move water to plants (d) spin a robot’s wheels
26. 26.True or false: to switch on lamps at dusk, use a soil moisture sensor. (a) True (b) False
27. 27.True or false: to stop a robot near walls, use a distance sensor. (a) True (b) False
28. 28.True or false: to keep an incubator warm, use a temperature sensor. (a) True (b) False
29. 29.True or false: to measure classroom noise, use a sound sensor. (a) True (b) False
30. 30.🔍 An object is 68 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
31. 31.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
32. 32.🔍 Which sensor would you use to make a parking alarm? (a) a sound sensor (b) a light sensor (c) a rain sensor (d) a distance sensor
33. 33.Which job needs a buzzer? (a) turn to an exact angle (b) show a status light (c) spin a robot’s wheels (d) beep an alarm
34. 34.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) a power source (c) an output (d) a fuse
35. 35.Which job needs a motor? (a) move water to plants (b) show the temperature (c) beep an alarm (d) spin a robot’s wheels
36. 36.⚙️ Which actuator would you use to beep an alarm? (a) an LED (b) a servo motor (c) a buzzer (d) a pump
37. 37.⚙️ Which actuator would you use to open a gate to 90°? (a) a pump (b) a display (c) a servo motor (d) a motor
38. 38.True or false: to switch on lamps at dusk, use a motion sensor. (a) False (b) True
39. 39.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a display (b) a buzzer (c) an LED (d) a motor
40. 40.Which job needs a light sensor? (a) keep an incubator warm (b) warn of a gas leak (c) close a window in rain (d) switch on lamps at dusk

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