Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 8 · 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 warn of a gas leak, use a rain sensor. (a) False (b) True
2. 2.Which job needs a buzzer? (a) open a gate to 90° (b) turn to an exact angle (c) show a status light (d) beep an alarm
3. 3.🔍 A distance sensor sends a sound pulse and hears the echo 8 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
4. 4.⚙️ What is an actuator? (a) a program (b) a sensor (c) a battery (d) an output that acts
5. 5.⚙️ Which actuator would you use to beep an alarm? (a) a display (b) a pump (c) a motor (d) a buzzer
6. 6.True or false: to water a dry plant, use a light sensor. (a) True (b) False
7. 7.Which job needs a motor? (a) show the temperature (b) move water to plants (c) spin a robot’s wheels (d) open a gate to 90°
8. 8.⚙️ Which actuator would you use to turn to an exact angle? (a) a buzzer (b) a pump (c) a servo motor (d) an LED
9. 9.🔍 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?
10. 10.Which job needs a distance sensor? (a) close a window in rain (b) spot someone walking in (c) open blinds at sunrise (d) stop a robot near walls
11. 11.True or false: to switch on lamps at dusk, use a motion sensor. (a) False (b) True
12. 12.🔍 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?
13. 13.Which job needs a soil moisture sensor? (a) close a window in rain (b) start a fan when hot (c) water a dry plant (d) switch on lamps at dusk
14. 14.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a pump (b) a display (c) an LED (d) a motor
15. 15.True or false: to water a dry plant, use a soil moisture sensor. (a) False (b) True
16. 16.Which job needs a distance sensor? (a) spot someone walking in (b) warn of a gas leak (c) switch on lamps at dusk (d) make a parking alarm
17. 17.Which job needs a sound sensor? (a) switch on lamps at dusk (b) close a window in rain (c) measure classroom noise (d) start a fan when hot
18. 18.Which job needs a pump? (a) show the temperature (b) move water to plants (c) spin a robot’s wheels (d) show a status light
19. 19.🔍 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?
20. 20.True or false: to measure classroom noise, use a rain sensor. (a) True (b) False
21. 21.🔍 Which sensor would you use to switch on with a clap? (a) a motion sensor (b) a rain sensor (c) a sound sensor (d) a light sensor
22. 22.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) a fuse (c) an input (d) an output
23. 23.Which job needs a rain sensor? (a) open blinds at sunrise (b) keep an incubator warm (c) close a window in rain (d) measure classroom noise
24. 24.🔍 Which sensor would you use to start a fan when hot? (a) a motion sensor (b) a temperature sensor (c) a distance sensor (d) a rain sensor
25. 25.🔍 Which sensor would you use to open blinds at sunrise? (a) a motion sensor (b) a sound sensor (c) a gas sensor (d) a light sensor
26. 26.True or false: to close a window in rain, use a gas sensor. (a) True (b) False
27. 27.🔍 An object is 187 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
28. 28.⚙️ Which actuator would you use to show a status light? (a) a motor (b) an LED (c) a display (d) a servo motor
29. 29.🔍 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)?
30. 30.🔍 A distance sensor sends a sound pulse and hears the echo 10 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
31. 31.🔍 Which sensor would you use to switch on lamps at dusk? (a) a motion sensor (b) a soil moisture sensor (c) a rain sensor (d) a light sensor
32. 32.Which job needs a light sensor? (a) start a fan when hot (b) measure classroom noise (c) warn of a gas leak (d) switch on lamps at dusk
33. 33.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
34. 34.Which job needs a servo motor? (a) show a status light (b) move water to plants (c) spin a robot’s wheels (d) turn to an exact angle
35. 35.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
36. 36.⚙️ Which actuator would you use to show the temperature? (a) a pump (b) a buzzer (c) an LED (d) a display
37. 37.Which job needs a display? (a) spin a robot’s wheels (b) turn to an exact angle (c) move water to plants (d) show the temperature
38. 38.🔍 Which sensor would you use to measure classroom noise? (a) a sound sensor (b) a temperature sensor (c) a rain sensor (d) a light sensor
39. 39.True or false: to switch on lamps at dusk, use a light sensor. (a) False (b) True
40. 40.Which job needs an LED? (a) show a status light (b) show the temperature (c) open a gate to 90° (d) move water to plants

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