Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 293 · 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 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
2. 2.🔍 Which sensor would you use to warn of a gas leak? (a) a gas sensor (b) a motion sensor (c) a light sensor (d) a rain sensor
3. 3.⚙️ What is an actuator? (a) a sensor (b) a battery (c) a program (d) an output that acts
4. 4.🔍 An object is 306 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
5. 5.Which job needs a servo motor? (a) show the temperature (b) show a status light (c) beep an alarm (d) turn to an exact angle
6. 6.True or false: to close a window in rain, use a rain sensor. (a) True (b) False
7. 7.⚙️ Which actuator would you use to turn to an exact angle? (a) a motor (b) a servo motor (c) a buzzer (d) an LED
8. 8.🔍 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?
9. 9.Which job needs a light sensor? (a) make a parking alarm (b) keep an incubator warm (c) switch on lamps at dusk (d) switch on with a clap
10. 10.Which job needs an LED? (a) show a status light (b) spin a robot’s wheels (c) show the temperature (d) move water to plants
11. 11.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
12. 12.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) an input (c) a fuse (d) a power source
13. 13.Which job needs a pump? (a) show a status light (b) turn to an exact angle (c) move water to plants (d) spin a robot’s wheels
14. 14.Which job needs a rain sensor? (a) switch on lamps at dusk (b) water a dry plant (c) close a window in rain (d) stop a robot near walls
15. 15.🔍 Which sensor would you use to switch on lamps at dusk? (a) a soil moisture sensor (b) a gas sensor (c) a sound sensor (d) a light sensor
16. 16.🔍 Which sensor would you use to open blinds at sunrise? (a) a rain sensor (b) a sound sensor (c) a temperature sensor (d) a light sensor
17. 17.Which job needs a display? (a) open a gate to 90° (b) show the temperature (c) spin a robot’s wheels (d) move water to plants
18. 18.🔍 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?
19. 19.⚙️ Which actuator would you use to show a status light? (a) an LED (b) a buzzer (c) a display (d) a servo motor
20. 20.🔍 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?
21. 21.🔍 Which sensor would you use to switch on with a clap? (a) a soil moisture sensor (b) a motion sensor (c) a sound sensor (d) a light sensor
22. 22.Which job needs a sound sensor? (a) stop a robot near walls (b) open blinds at sunrise (c) start a fan when hot (d) switch on with a clap
23. 23.🔍 Which sensor would you use to measure classroom noise? (a) a light sensor (b) a distance sensor (c) a gas sensor (d) a sound sensor
24. 24.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
25. 25.🔍 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?
26. 26.True or false: to spot someone walking in, use a motion sensor. (a) True (b) False
27. 27.⚙️ Which actuator would you use to move water to plants? (a) an LED (b) a buzzer (c) a display (d) a pump
28. 28.True or false: to warn of a gas leak, use a gas sensor. (a) False (b) True
29. 29.True or false: to open blinds at sunrise, use a temperature sensor. (a) False (b) True
30. 30.True or false: to switch on lamps at dusk, use a gas sensor. (a) True (b) False
31. 31.🔍 Which sensor would you use to stop a robot near walls? (a) a soil moisture sensor (b) a sound sensor (c) a motion sensor (d) a distance sensor
32. 32.Which job needs a sound sensor? (a) open blinds at sunrise (b) switch on lamps at dusk (c) measure classroom noise (d) water a dry plant
33. 33.🔍 Which sensor would you use to start a fan when hot? (a) a distance sensor (b) a light sensor (c) a sound sensor (d) a temperature sensor
34. 34.Which job needs a gas sensor? (a) start a fan when hot (b) keep an incubator warm (c) measure classroom noise (d) warn of a gas leak
35. 35.Which job needs a motion sensor? (a) start a fan when hot (b) spot someone walking in (c) switch on lamps at dusk (d) make a parking alarm
36. 36.⚙️ Which actuator would you use to beep an alarm? (a) a display (b) a servo motor (c) a buzzer (d) a pump
37. 37.⚙️ Which actuator would you use to open a gate to 90°? (a) a servo motor (b) a motor (c) an LED (d) a buzzer
38. 38.Which job needs a buzzer? (a) move water to plants (b) open a gate to 90° (c) beep an alarm (d) show the temperature
39. 39.Which job needs a motor? (a) show the temperature (b) beep an alarm (c) open a gate to 90° (d) spin a robot’s wheels
40. 40.🔍 Which sensor would you use to spot someone walking in? (a) a gas sensor (b) a motion sensor (c) a light sensor (d) a sound sensor

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