Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 332 · 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.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) an input (c) a power source (d) a fuse
2. 2.True or false: to switch on with a clap, use a motion sensor. (a) False (b) True
3. 3.True or false: to stop a robot near walls, use a sound sensor. (a) False (b) True
4. 4.True or false: to start a fan when hot, use a rain sensor. (a) True (b) False
5. 5.True or false: to water a dry plant, use a soil moisture sensor. (a) False (b) True
6. 6.⚙️ Which actuator would you use to turn to an exact angle? (a) a motor (b) a buzzer (c) an LED (d) a servo motor
7. 7.Which job needs an LED? (a) turn to an exact angle (b) spin a robot’s wheels (c) show a status light (d) move water to plants
8. 8.🔍 Which sensor would you use to measure classroom noise? (a) a rain sensor (b) a sound sensor (c) a light sensor (d) a temperature sensor
9. 9.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a pump (c) a display (d) a motor
10. 10.🔍 An object is 340 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
11. 11.⚙️ What is an actuator? (a) an output that acts (b) a battery (c) a program (d) a sensor
12. 12.⚙️ Which actuator would you use to open a gate to 90°? (a) an LED (b) a servo motor (c) a display (d) a buzzer
13. 13.True or false: to start a fan when hot, use a sound sensor. (a) True (b) False
14. 14.🔍 Which sensor would you use to water a dry plant? (a) a gas sensor (b) a soil moisture sensor (c) a light sensor (d) a distance sensor
15. 15.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
16. 16.Which job needs a servo motor? (a) spin a robot’s wheels (b) open a gate to 90° (c) beep an alarm (d) show the temperature
17. 17.⚙️ Which actuator would you use to spin a robot’s wheels? (a) an LED (b) a motor (c) a display (d) a pump
18. 18.🔍 A distance sensor sends a sound pulse and hears the echo 12 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
19. 19.🔍 Which sensor would you use to keep an incubator warm? (a) a soil moisture sensor (b) a distance sensor (c) a temperature sensor (d) a sound sensor
20. 20.True or false: to switch on with a clap, use a light sensor. (a) True (b) False
21. 21.🔍 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)?
22. 22.Which job needs a distance sensor? (a) keep an incubator warm (b) stop a robot near walls (c) measure classroom noise (d) open blinds at sunrise
23. 23.Which job needs a light sensor? (a) switch on lamps at dusk (b) stop a robot near walls (c) start a fan when hot (d) keep an incubator warm
24. 24.Which job needs a light sensor? (a) open blinds at sunrise (b) spot someone walking in (c) make a parking alarm (d) warn of a gas leak
25. 25.True or false: to open blinds at sunrise, use a rain sensor. (a) True (b) False
26. 26.Which job needs a gas sensor? (a) switch on with a clap (b) open blinds at sunrise (c) warn of a gas leak (d) keep an incubator warm
27. 27.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
28. 28.🔍 Which sensor would you use to start a fan when hot? (a) a temperature sensor (b) a rain sensor (c) a sound sensor (d) a soil moisture sensor
29. 29.🔍 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)?
30. 30.🔍 Which sensor would you use to warn of a gas leak? (a) a soil moisture sensor (b) a temperature sensor (c) a sound sensor (d) a gas sensor
31. 31.Which job needs a sound sensor? (a) close a window in rain (b) switch on with a clap (c) warn of a gas leak (d) stop a robot near walls
32. 32.Which job needs a sound sensor? (a) measure classroom noise (b) open blinds at sunrise (c) water a dry plant (d) make a parking alarm
33. 33.Which job needs a buzzer? (a) spin a robot’s wheels (b) show a status light (c) beep an alarm (d) move water to plants
34. 34.🔍 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?
35. 35.True or false: to switch on with a clap, use a temperature sensor. (a) False (b) True
36. 36.🔍 Which sensor would you use to spot someone walking in? (a) a distance sensor (b) a sound sensor (c) a motion sensor (d) a light sensor
37. 37.True or false: to warn of a gas leak, use a gas sensor. (a) False (b) True
38. 38.True or false: to stop a robot near walls, use a distance sensor. (a) True (b) False
39. 39.Which job needs a display? (a) show the temperature (b) show a status light (c) beep an alarm (d) open a gate to 90°
40. 40.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False

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