Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 141 · 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.🔍 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)?
2. 2.⚙️ Which actuator would you use to show a status light? (a) a display (b) an LED (c) a pump (d) a servo motor
3. 3.⚙️ What is an actuator? (a) a program (b) a sensor (c) a battery (d) an output that acts
4. 4.Which job needs a display? (a) open a gate to 90° (b) move water to plants (c) show the temperature (d) show a status light
5. 5.🔍 Which sensor would you use to close a window in rain? (a) a soil moisture sensor (b) a temperature sensor (c) a sound sensor (d) a rain sensor
6. 6.True or false: to switch on lamps at dusk, use a light sensor. (a) False (b) True
7. 7.🔍 Which sensor would you use to warn of a gas leak? (a) a rain sensor (b) a light sensor (c) a gas sensor (d) a distance sensor
8. 8.🔍 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)?
9. 9.Which job needs a soil moisture sensor? (a) start a fan when hot (b) stop a robot near walls (c) spot someone walking in (d) water a dry plant
10. 10.Which job needs a motor? (a) show a status light (b) beep an alarm (c) move water to plants (d) spin a robot’s wheels
11. 11.True or false: to make a parking alarm, use a motion sensor. (a) False (b) True
12. 12.🔍 Which sensor would you use to measure classroom noise? (a) a light sensor (b) a soil moisture sensor (c) a temperature sensor (d) a sound sensor
13. 13.🔍 An object is 51 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
14. 14.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) an input (c) an output (d) a power source
15. 15.True or false: to keep an incubator warm, use a temperature sensor. (a) True (b) False
16. 16.🔍 Which sensor would you use to make a parking alarm? (a) a gas sensor (b) a rain sensor (c) a light sensor (d) a distance sensor
17. 17.🔍 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?
18. 18.🔍 Which sensor would you use to keep an incubator warm? (a) a sound sensor (b) a temperature sensor (c) a light sensor (d) a gas sensor
19. 19.Which job needs a light sensor? (a) spot someone walking in (b) stop a robot near walls (c) switch on lamps at dusk (d) make a parking alarm
20. 20.Which job needs a gas sensor? (a) make a parking alarm (b) warn of a gas leak (c) open blinds at sunrise (d) water a dry plant
21. 21.🔍 Which sensor would you use to switch on with a clap? (a) a temperature sensor (b) a light sensor (c) a rain sensor (d) a sound sensor
22. 22.⚙️ Which actuator would you use to turn to an exact angle? (a) a motor (b) an LED (c) a servo motor (d) a buzzer
23. 23.🔍 Which sensor would you use to spot someone walking in? (a) a sound sensor (b) a motion sensor (c) a gas sensor (d) a distance sensor
24. 24.🔍 An object is 255 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
25. 25.🔍 A distance sensor sends a sound pulse and hears the echo 5 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
26. 26.🔍 Which sensor would you use to water a dry plant? (a) a soil moisture sensor (b) a rain sensor (c) a light sensor (d) a distance sensor
27. 27.Which job needs a sound sensor? (a) measure classroom noise (b) close a window in rain (c) switch on lamps at dusk (d) water a dry plant
28. 28.Which job needs a servo motor? (a) spin a robot’s wheels (b) turn to an exact angle (c) show the temperature (d) move water to plants
29. 29.True or false: to water a dry plant, use a temperature sensor. (a) True (b) False
30. 30.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
31. 31.⚙️ Which actuator would you use to move water to plants? (a) an LED (b) a buzzer (c) a pump (d) a motor
32. 32.True or false: to switch on lamps at dusk, use a distance sensor. (a) False (b) True
33. 33.🔍 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?
34. 34.Which job needs a rain sensor? (a) spot someone walking in (b) measure classroom noise (c) open blinds at sunrise (d) close a window in rain
35. 35.⚙️ Which actuator would you use to open a gate to 90°? (a) a display (b) a motor (c) a servo motor (d) a buzzer
36. 36.🔍 A distance sensor sends a sound pulse and hears the echo 13 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
37. 37.True or false: to water a dry plant, use a light sensor. (a) False (b) True
38. 38.Which job needs an LED? (a) show the temperature (b) open a gate to 90° (c) show a status light (d) spin a robot’s wheels
39. 39.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a motion sensor (c) a light sensor (d) a rain sensor
40. 40.⚙️ Which actuator would you use to show the temperature? (a) a pump (b) a servo motor (c) an LED (d) a display

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