Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 284 · 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.🔍 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?
2. 2.Which job needs a light sensor? (a) measure classroom noise (b) open blinds at sunrise (c) switch on with a clap (d) stop a robot near walls
3. 3.Which job needs a rain sensor? (a) close a window in rain (b) switch on lamps at dusk (c) warn of a gas leak (d) start a fan when hot
4. 4.Which job needs a soil moisture sensor? (a) start a fan when hot (b) switch on lamps at dusk (c) warn of a gas leak (d) water a dry plant
5. 5.🔍 Which sensor would you use to stop a robot near walls? (a) a temperature sensor (b) a light sensor (c) a distance sensor (d) a motion sensor
6. 6.🔍 A distance sensor sends a sound pulse and hears the echo 15 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
7. 7.⚙️ Which actuator would you use to move water to plants? (a) a pump (b) a buzzer (c) a motor (d) an LED
8. 8.Which job needs a sound sensor? (a) measure classroom noise (b) switch on lamps at dusk (c) stop a robot near walls (d) make a parking alarm
9. 9.🔍 Which sensor would you use to warn of a gas leak? (a) a rain sensor (b) a gas sensor (c) a distance sensor (d) a soil moisture sensor
10. 10.Which job needs a distance sensor? (a) spot someone walking in (b) start a fan when hot (c) stop a robot near walls (d) warn of a gas leak
11. 11.True or false: to switch on with a clap, use a sound sensor. (a) False (b) True
12. 12.🔍 Which sensor would you use to close a window in rain? (a) a soil moisture sensor (b) a gas sensor (c) a light sensor (d) a rain sensor
13. 13.🔍 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?
14. 14.🔍 Which sensor would you use to keep an incubator warm? (a) a sound sensor (b) a gas sensor (c) a temperature sensor (d) a distance sensor
15. 15.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
16. 16.Which job needs a buzzer? (a) turn to an exact angle (b) show a status light (c) beep an alarm (d) open a gate to 90°
17. 17.Which job needs a motion sensor? (a) open blinds at sunrise (b) start a fan when hot (c) switch on lamps at dusk (d) spot someone walking in
18. 18.⚙️ What is an actuator? (a) a sensor (b) a battery (c) an output that acts (d) a program
19. 19.Which job needs a pump? (a) turn to an exact angle (b) show a status light (c) open a gate to 90° (d) move water to plants
20. 20.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an input (d) an output
21. 21.True or false: to warn of a gas leak, use a gas sensor. (a) True (b) False
22. 22.Which job needs a display? (a) turn to an exact angle (b) show a status light (c) show the temperature (d) spin a robot’s wheels
23. 23.True or false: to start a fan when hot, use a sound sensor. (a) True (b) False
24. 24.Which job needs an LED? (a) show the temperature (b) show a status light (c) beep an alarm (d) turn to an exact angle
25. 25.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) a pump (c) an LED (d) a motor
26. 26.Which job needs a servo motor? (a) spin a robot’s wheels (b) show the temperature (c) show a status light (d) open a gate to 90°
27. 27.🔍 Which sensor would you use to switch on with a clap? (a) a sound sensor (b) a gas sensor (c) a motion sensor (d) a distance sensor
28. 28.Which job needs a sound sensor? (a) switch on with a clap (b) switch on lamps at dusk (c) keep an incubator warm (d) warn of a gas leak
29. 29.🔍 Which sensor would you use to switch on lamps at dusk? (a) a light sensor (b) a rain sensor (c) a sound sensor (d) a distance sensor
30. 30.🔍 Which sensor would you use to start a fan when hot? (a) a motion sensor (b) a temperature sensor (c) a distance sensor (d) a light sensor
31. 31.🔍 An object is 204 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
32. 32.Which job needs a temperature sensor? (a) switch on lamps at dusk (b) stop a robot near walls (c) keep an incubator warm (d) warn of a gas leak
33. 33.True or false: to start a fan when hot, use a motion sensor. (a) True (b) False
34. 34.🔍 An object is 136 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
35. 35.🔍 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)?
36. 36.⚙️ Which actuator would you use to turn to an exact angle? (a) a display (b) a pump (c) a servo motor (d) a motor
37. 37.⚙️ Which actuator would you use to show the temperature? (a) a servo motor (b) a motor (c) a display (d) an LED
38. 38.🔍 An object is 17 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
39. 39.🔍 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)?
40. 40.True or false: to keep an incubator warm, use a light sensor. (a) True (b) False

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