Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 224 · 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 17 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
2. 2.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
3. 3.⚙️ What is an actuator? (a) a battery (b) a program (c) a sensor (d) an output that acts
4. 4.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a servo motor (c) a buzzer (d) a motor
5. 5.Which job needs a servo motor? (a) open a gate to 90° (b) show the temperature (c) move water to plants (d) spin a robot’s wheels
6. 6.🔍 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)?
7. 7.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
8. 8.True or false: to keep an incubator warm, use a temperature sensor. (a) False (b) True
9. 9.True or false: to switch on with a clap, use a rain sensor. (a) True (b) False
10. 10.🔍 Which sensor would you use to open blinds at sunrise? (a) a gas sensor (b) a sound sensor (c) a light sensor (d) a motion sensor
11. 11.🔍 Which sensor would you use to stop a robot near walls? (a) a soil moisture sensor (b) a motion sensor (c) a distance sensor (d) a sound sensor
12. 12.Which job needs a sound sensor? (a) stop a robot near walls (b) start a fan when hot (c) open blinds at sunrise (d) switch on with a clap
13. 13.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a servo motor (c) an LED (d) a pump
14. 14.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) an output (c) an input (d) a power source
15. 15.🔍 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)?
16. 16.Which job needs a distance sensor? (a) make a parking alarm (b) open blinds at sunrise (c) warn of a gas leak (d) switch on lamps at dusk
17. 17.🔍 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?
18. 18.True or false: to keep an incubator warm, use a gas sensor. (a) True (b) False
19. 19.Which job needs a gas sensor? (a) keep an incubator warm (b) close a window in rain (c) open blinds at sunrise (d) warn of a gas leak
20. 20.Which job needs a temperature sensor? (a) open blinds at sunrise (b) make a parking alarm (c) stop a robot near walls (d) keep an incubator warm
21. 21.⚙️ Which actuator would you use to show a status light? (a) a motor (b) a display (c) an LED (d) a pump
22. 22.Which job needs a buzzer? (a) show a status light (b) open a gate to 90° (c) spin a robot’s wheels (d) beep an alarm
23. 23.Which job needs a rain sensor? (a) close a window in rain (b) switch on with a clap (c) start a fan when hot (d) switch on lamps at dusk
24. 24.Which job needs a light sensor? (a) measure classroom noise (b) start a fan when hot (c) switch on lamps at dusk (d) spot someone walking in
25. 25.🔍 Which sensor would you use to switch on lamps at dusk? (a) a motion sensor (b) a light sensor (c) a soil moisture sensor (d) a rain sensor
26. 26.🔍 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?
27. 27.⚙️ Which actuator would you use to turn to an exact angle? (a) a buzzer (b) a display (c) an LED (d) a servo motor
28. 28.🔍 A distance sensor sends a sound pulse and hears the echo 1 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
29. 29.⚙️ Which actuator would you use to move water to plants? (a) a motor (b) a pump (c) a servo motor (d) a display
30. 30.🔍 A distance sensor sends a sound pulse and hears the echo 9 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
31. 31.🔍 Which sensor would you use to keep an incubator warm? (a) a light sensor (b) a sound sensor (c) a temperature sensor (d) a gas sensor
32. 32.Which job needs a servo motor? (a) turn to an exact angle (b) spin a robot’s wheels (c) show the temperature (d) beep an alarm
33. 33.🔍 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)?
34. 34.🔍 Which sensor would you use to water a dry plant? (a) a motion sensor (b) a sound sensor (c) a distance sensor (d) a soil moisture sensor
35. 35.Which job needs a soil moisture sensor? (a) make a parking alarm (b) spot someone walking in (c) open blinds at sunrise (d) water a dry plant
36. 36.True or false: to switch on with a clap, use a distance sensor. (a) True (b) False
37. 37.🔍 Which sensor would you use to start a fan when hot? (a) a soil moisture sensor (b) a temperature sensor (c) a motion sensor (d) a rain sensor
38. 38.🔍 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)?
39. 39.True or false: to water a dry plant, use a motion sensor. (a) True (b) False
40. 40.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a servo motor (b) a motor (c) an LED (d) a buzzer

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