Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 75 · 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 light sensor? (a) spot someone walking in (b) open blinds at sunrise (c) water a dry plant (d) warn of a gas leak
2. 2.🔍 Which sensor would you use to water a dry plant? (a) a soil moisture sensor (b) a light sensor (c) a motion sensor (d) a sound sensor
3. 3.🔍 An object is 153 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
4. 4.⚙️ Which actuator would you use to open a gate to 90°? (a) a display (b) a servo motor (c) a motor (d) an LED
5. 5.🔍 Which sensor would you use to start a fan when hot? (a) a distance sensor (b) a motion sensor (c) a temperature sensor (d) a soil moisture sensor
6. 6.Which job needs a motor? (a) open a gate to 90° (b) spin a robot’s wheels (c) turn to an exact angle (d) move water to plants
7. 7.Which job needs a soil moisture sensor? (a) stop a robot near walls (b) water a dry plant (c) start a fan when hot (d) open blinds at sunrise
8. 8.Which job needs a light sensor? (a) switch on lamps at dusk (b) warn of a gas leak (c) water a dry plant (d) keep an incubator warm
9. 9.🔍 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?
10. 10.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) an output (c) a power source (d) a fuse
11. 11.⚙️ What is an actuator? (a) a sensor (b) a battery (c) a program (d) an output that acts
12. 12.Which job needs a motion sensor? (a) spot someone walking in (b) make a parking alarm (c) switch on with a clap (d) switch on lamps at dusk
13. 13.Which job needs a buzzer? (a) turn to an exact angle (b) spin a robot’s wheels (c) beep an alarm (d) open a gate to 90°
14. 14.Which job needs an LED? (a) move water to plants (b) turn to an exact angle (c) show a status light (d) beep an alarm
15. 15.Which job needs a servo motor? (a) open a gate to 90° (b) show the temperature (c) spin a robot’s wheels (d) beep an alarm
16. 16.True or false: to water a dry plant, use a gas sensor. (a) False (b) True
17. 17.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
18. 18.🔍 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?
19. 19.🔍 Which sensor would you use to open blinds at sunrise? (a) a rain sensor (b) a motion sensor (c) a light sensor (d) a distance sensor
20. 20.Which job needs a pump? (a) move water to plants (b) beep an alarm (c) show the temperature (d) spin a robot’s wheels
21. 21.🔍 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)?
22. 22.⚙️ Which actuator would you use to show a status light? (a) a servo motor (b) a motor (c) a buzzer (d) an LED
23. 23.True or false: to measure classroom noise, use a gas sensor. (a) False (b) True
24. 24.🔍 A distance sensor sends a sound pulse and hears the echo 6 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
25. 25.🔍 Which sensor would you use to keep an incubator warm? (a) a rain sensor (b) a soil moisture sensor (c) a temperature sensor (d) a light sensor
26. 26.Which job needs a display? (a) spin a robot’s wheels (b) beep an alarm (c) show the temperature (d) move water to plants
27. 27.True or false: to start a fan when hot, use a light sensor. (a) True (b) False
28. 28.🔍 A distance sensor sends a sound pulse and hears the echo 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
29. 29.🔍 A distance sensor sends a sound pulse and hears the echo 16 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 2 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
31. 31.True or false: to start a fan when hot, use a soil moisture sensor. (a) True (b) False
32. 32.🔍 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)?
33. 33.True or false: to spot someone walking in, use a gas sensor. (a) True (b) False
34. 34.🔍 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)?
35. 35.Which job needs a gas sensor? (a) warn of a gas leak (b) switch on with a clap (c) stop a robot near walls (d) water a dry plant
36. 36.🔍 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?
37. 37.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
38. 38.🔍 Which sensor would you use to make a parking alarm? (a) a distance sensor (b) a light sensor (c) a sound sensor (d) a gas sensor
39. 39.🔍 Which sensor would you use to switch on lamps at dusk? (a) a light sensor (b) a motion sensor (c) a sound sensor (d) a temperature sensor
40. 40.⚙️ Which actuator would you use to move water to plants? (a) a pump (b) a display (c) a servo motor (d) an LED

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