Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 98 · 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 19 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 spin a robot’s wheels? (a) a motor (b) a buzzer (c) a display (d) a pump
3. 3.Which job needs a soil moisture sensor? (a) measure classroom noise (b) switch on lamps at dusk (c) water a dry plant (d) make a parking alarm
4. 4.True or false: to water a dry plant, use a soil moisture sensor. (a) False (b) True
5. 5.🔍 A distance sensor sends a sound pulse and hears the echo 18 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
6. 6.Which job needs a light sensor? (a) stop a robot near walls (b) warn of a gas leak (c) switch on lamps at dusk (d) close a window in rain
7. 7.🔍 Which sensor would you use to switch on lamps at dusk? (a) a sound sensor (b) a distance sensor (c) a soil moisture sensor (d) a light sensor
8. 8.Which job needs a buzzer? (a) spin a robot’s wheels (b) turn to an exact angle (c) move water to plants (d) beep an alarm
9. 9.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a fuse (c) an input (d) a power source
10. 10.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) an LED (c) a motor (d) a pump
11. 11.⚙️ What is an actuator? (a) a program (b) a sensor (c) a battery (d) an output that acts
12. 12.⚙️ Which actuator would you use to open a gate to 90°? (a) a display (b) a motor (c) a servo motor (d) a pump
13. 13.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
14. 14.True or false: to close a window in rain, use a gas sensor. (a) True (b) False
15. 15.🔍 Which sensor would you use to measure classroom noise? (a) a sound sensor (b) a light sensor (c) a motion sensor (d) a distance sensor
16. 16.Which job needs a sound sensor? (a) make a parking alarm (b) spot someone walking in (c) measure classroom noise (d) stop a robot near walls
17. 17.True or false: to switch on with a clap, use a soil moisture sensor. (a) False (b) True
18. 18.🔍 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?
19. 19.Which job needs an LED? (a) turn to an exact angle (b) open a gate to 90° (c) beep an alarm (d) show a status light
20. 20.⚙️ Which actuator would you use to show a status light? (a) a buzzer (b) a pump (c) a servo motor (d) an LED
21. 21.🔍 Which sensor would you use to switch on with a clap? (a) a soil moisture sensor (b) a motion sensor (c) a temperature sensor (d) a sound sensor
22. 22.🔍 Which sensor would you use to open blinds at sunrise? (a) a distance sensor (b) a motion sensor (c) a light sensor (d) a temperature sensor
23. 23.Which job needs a light sensor? (a) open blinds at sunrise (b) stop a robot near walls (c) spot someone walking in (d) switch on with a clap
24. 24.Which job needs a gas sensor? (a) keep an incubator warm (b) open blinds at sunrise (c) switch on lamps at dusk (d) warn of a gas leak
25. 25.Which job needs a rain sensor? (a) spot someone walking in (b) close a window in rain (c) stop a robot near walls (d) switch on lamps at dusk
26. 26.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
27. 27.🔍 Which sensor would you use to make a parking alarm? (a) a light sensor (b) a distance sensor (c) a sound sensor (d) a rain sensor
28. 28.True or false: to make a parking alarm, use a distance sensor. (a) True (b) False
29. 29.Which job needs a motion sensor? (a) keep an incubator warm (b) spot someone walking in (c) stop a robot near walls (d) warn of a gas leak
30. 30.True or false: to make a parking alarm, use a temperature sensor. (a) True (b) False
31. 31.🔍 Which sensor would you use to water a dry plant? (a) a sound sensor (b) a soil moisture sensor (c) a rain sensor (d) a light sensor
32. 32.🔍 An object is 272 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
33. 33.🔍 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?
34. 34.🔍 An object is 34 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
35. 35.Which job needs a pump? (a) move water to plants (b) show a status light (c) open a gate to 90° (d) show the temperature
36. 36.True or false: to keep an incubator warm, use a motion sensor. (a) True (b) False
37. 37.⚙️ Which actuator would you use to show the temperature? (a) a servo motor (b) a display (c) a motor (d) a buzzer
38. 38.🔍 Which sensor would you use to keep an incubator warm? (a) a motion sensor (b) a temperature sensor (c) a distance sensor (d) a light sensor
39. 39.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
40. 40.⚙️ Which actuator would you use to turn to an exact angle? (a) an LED (b) a servo motor (c) a motor (d) a buzzer

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