Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 182 · 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) a power source (b) an output (c) a fuse (d) an input
2. 2.🔍 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)?
3. 3.⚙️ Which actuator would you use to move water to plants? (a) a display (b) a pump (c) a buzzer (d) a motor
4. 4.Which job needs a gas sensor? (a) close a window in rain (b) warn of a gas leak (c) keep an incubator warm (d) open blinds at sunrise
5. 5.🔍 Which sensor would you use to make a parking alarm? (a) a temperature sensor (b) a sound sensor (c) a soil moisture sensor (d) a distance sensor
6. 6.Which job needs a servo motor? (a) show the temperature (b) spin a robot’s wheels (c) show a status light (d) open a gate to 90°
7. 7.🔍 An object is 102 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
8. 8.Which job needs a display? (a) show the temperature (b) show a status light (c) beep an alarm (d) move water to plants
9. 9.Which job needs a rain sensor? (a) keep an incubator warm (b) stop a robot near walls (c) close a window in rain (d) start a fan when hot
10. 10.Which job needs a motion sensor? (a) open blinds at sunrise (b) spot someone walking in (c) stop a robot near walls (d) keep an incubator warm
11. 11.Which job needs a motor? (a) open a gate to 90° (b) show the temperature (c) spin a robot’s wheels (d) turn to an exact angle
12. 12.🔍 Which sensor would you use to open blinds at sunrise? (a) a light sensor (b) a gas sensor (c) a temperature sensor (d) a motion sensor
13. 13.🔍 Which sensor would you use to measure classroom noise? (a) a temperature sensor (b) a light sensor (c) a sound sensor (d) a gas sensor
14. 14.🔍 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)?
15. 15.Which job needs a pump? (a) show a status light (b) move water to plants (c) spin a robot’s wheels (d) beep an alarm
16. 16.Which job needs a temperature sensor? (a) close a window in rain (b) open blinds at sunrise (c) warn of a gas leak (d) start a fan when hot
17. 17.🔍 A distance sensor sends a sound pulse and hears the echo 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
18. 18.Which job needs a sound sensor? (a) switch on lamps at dusk (b) make a parking alarm (c) open blinds at sunrise (d) measure classroom noise
19. 19.True or false: to warn of a gas leak, use a gas sensor. (a) False (b) True
20. 20.True or false: to close a window in rain, use a rain sensor. (a) True (b) False
21. 21.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
22. 22.Which job needs a buzzer? (a) show a status light (b) beep an alarm (c) move water to plants (d) turn to an exact angle
23. 23.🔍 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)?
24. 24.Which job needs an LED? (a) move water to plants (b) beep an alarm (c) show a status light (d) spin a robot’s wheels
25. 25.🔍 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?
26. 26.Which job needs a light sensor? (a) measure classroom noise (b) switch on with a clap (c) close a window in rain (d) switch on lamps at dusk
27. 27.⚙️ What is an actuator? (a) a program (b) an output that acts (c) a sensor (d) a battery
28. 28.⚙️ Which actuator would you use to beep an alarm? (a) a servo motor (b) a display (c) a buzzer (d) a motor
29. 29.🔍 Which sensor would you use to water a dry plant? (a) a motion sensor (b) a distance sensor (c) a gas sensor (d) a soil moisture sensor
30. 30.🔍 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?
31. 31.⚙️ Which actuator would you use to show a status light? (a) a display (b) a motor (c) an LED (d) a buzzer
32. 32.🔍 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)?
33. 33.🔍 A distance sensor sends a sound pulse and hears the echo 3 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
34. 34.True or false: to keep an incubator warm, use a light sensor. (a) False (b) True
35. 35.🔍 Which sensor would you use to stop a robot near walls? (a) a soil moisture sensor (b) a distance sensor (c) a gas sensor (d) a light sensor
36. 36.Which job needs a light sensor? (a) spot someone walking in (b) measure classroom noise (c) open blinds at sunrise (d) water a dry plant
37. 37.🔍 Which sensor would you use to start a fan when hot? (a) a distance sensor (b) a rain sensor (c) a motion sensor (d) a temperature sensor
38. 38.Which job needs a soil moisture sensor? (a) make a parking alarm (b) water a dry plant (c) stop a robot near walls (d) measure classroom noise
39. 39.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
40. 40.Which job needs a sound sensor? (a) make a parking alarm (b) warn of a gas leak (c) switch on with a clap (d) close a window in rain

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