Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 23 · 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) stop a robot near walls (c) keep an incubator warm (d) switch on lamps at dusk
2. 2.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) an input (c) a power source (d) a fuse
3. 3.Which job needs a servo motor? (a) move water to plants (b) turn to an exact angle (c) show the temperature (d) beep an alarm
4. 4.🔍 Which sensor would you use to spot someone walking in? (a) a gas sensor (b) a distance sensor (c) a motion sensor (d) a light sensor
5. 5.⚙️ What is an actuator? (a) a sensor (b) an output that acts (c) a program (d) a battery
6. 6.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) a pump (c) a motor (d) an LED
7. 7.🔍 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)?
8. 8.⚙️ Which actuator would you use to show the temperature? (a) a motor (b) an LED (c) a buzzer (d) a display
9. 9.Which job needs a sound sensor? (a) close a window in rain (b) water a dry plant (c) switch on with a clap (d) start a fan when hot
10. 10.🔍 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?
11. 11.Which job needs a light sensor? (a) switch on with a clap (b) open blinds at sunrise (c) water a dry plant (d) start a fan when hot
12. 12.🔍 An object is 119 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
13. 13.⚙️ Which actuator would you use to beep an alarm? (a) a pump (b) an LED (c) a buzzer (d) a servo motor
14. 14.Which job needs a distance sensor? (a) start a fan when hot (b) close a window in rain (c) stop a robot near walls (d) switch on with a clap
15. 15.🔍 Which sensor would you use to stop a robot near walls? (a) a rain sensor (b) a light sensor (c) a distance sensor (d) a soil moisture sensor
16. 16.Which job needs a rain sensor? (a) spot someone walking in (b) close a window in rain (c) measure classroom noise (d) open blinds at sunrise
17. 17.True or false: to switch on with a clap, use a sound sensor. (a) False (b) True
18. 18.True or false: to stop a robot near walls, use a distance sensor. (a) True (b) False
19. 19.Which job needs a distance sensor? (a) close a window in rain (b) water a dry plant (c) make a parking alarm (d) switch on with a clap
20. 20.🔍 Which sensor would you use to start a fan when hot? (a) a sound sensor (b) a temperature sensor (c) a light sensor (d) a soil moisture sensor
21. 21.True or false: to open blinds at sunrise, use a light sensor. (a) True (b) False
22. 22.True or false: to measure classroom noise, use a rain sensor. (a) False (b) True
23. 23.⚙️ Which actuator would you use to show a status light? (a) an LED (b) a servo motor (c) a motor (d) a buzzer
24. 24.🔍 Which sensor would you use to switch on lamps at dusk? (a) a gas sensor (b) a rain sensor (c) a soil moisture sensor (d) a light sensor
25. 25.🔍 Which sensor would you use to make a parking alarm? (a) a light sensor (b) a sound sensor (c) a distance sensor (d) a rain sensor
26. 26.Which job needs a soil moisture sensor? (a) keep an incubator warm (b) water a dry plant (c) make a parking alarm (d) stop a robot near walls
27. 27.🔍 Which sensor would you use to water a dry plant? (a) a soil moisture sensor (b) a sound sensor (c) a gas sensor (d) a distance sensor
28. 28.Which job needs a gas sensor? (a) start a fan when hot (b) warn of a gas leak (c) keep an incubator warm (d) make a parking alarm
29. 29.Which job needs a pump? (a) beep an alarm (b) move water to plants (c) spin a robot’s wheels (d) turn to an exact angle
30. 30.🔍 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?
31. 31.🔍 An object is 68 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
32. 32.🔍 A distance sensor sends a sound pulse and hears the echo 20 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
33. 33.⚙️ Which actuator would you use to turn to an exact angle? (a) a pump (b) an LED (c) a display (d) a servo motor
34. 34.🔍 Which sensor would you use to open blinds at sunrise? (a) a motion sensor (b) a soil moisture sensor (c) a light sensor (d) a distance sensor
35. 35.Which job needs a buzzer? (a) open a gate to 90° (b) beep an alarm (c) show a status light (d) move water to plants
36. 36.Which job needs a display? (a) turn to an exact angle (b) show the temperature (c) open a gate to 90° (d) show a status light
37. 37.Which job needs a servo motor? (a) open a gate to 90° (b) beep an alarm (c) move water to plants (d) spin a robot’s wheels
38. 38.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
39. 39.🔍 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)?
40. 40.⚙️ Which actuator would you use to move water to plants? (a) an LED (b) a buzzer (c) a pump (d) a display

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