Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 30 · 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 motion sensor? (a) start a fan when hot (b) open blinds at sunrise (c) spot someone walking in (d) switch on lamps at dusk
2. 2.🔍 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?
3. 3.🔍 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)?
4. 4.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an input (c) an output (d) a fuse
5. 5.🔍 Which sensor would you use to switch on lamps at dusk? (a) a sound sensor (b) a temperature sensor (c) a light sensor (d) a rain sensor
6. 6.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a motor (b) a pump (c) an LED (d) a display
7. 7.⚙️ Which actuator would you use to move water to plants? (a) a display (b) an LED (c) a motor (d) a pump
8. 8.🔍 Which sensor would you use to switch on with a clap? (a) a distance sensor (b) a motion sensor (c) a sound sensor (d) a gas sensor
9. 9.⚙️ Which actuator would you use to turn to an exact angle? (a) a pump (b) a motor (c) a buzzer (d) a servo motor
10. 10.Which job needs a pump? (a) turn to an exact angle (b) move water to plants (c) beep an alarm (d) show the temperature
11. 11.⚙️ What is an actuator? (a) a battery (b) a program (c) an output that acts (d) a sensor
12. 12.Which job needs a soil moisture sensor? (a) measure classroom noise (b) water a dry plant (c) start a fan when hot (d) warn of a gas leak
13. 13.⚙️ Which actuator would you use to show a status light? (a) a buzzer (b) an LED (c) a display (d) a motor
14. 14.Which job needs a servo motor? (a) move water to plants (b) beep an alarm (c) show a status light (d) open a gate to 90°
15. 15.🔍 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?
16. 16.True or false: to warn of a gas leak, use a gas sensor. (a) False (b) True
17. 17.Which job needs a gas sensor? (a) close a window in rain (b) water a dry plant (c) warn of a gas leak (d) spot someone walking in
18. 18.Which job needs a light sensor? (a) water a dry plant (b) keep an incubator warm (c) open blinds at sunrise (d) make a parking alarm
19. 19.🔍 An object is 153 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
20. 20.Which job needs a light sensor? (a) keep an incubator warm (b) water a dry plant (c) warn of a gas leak (d) switch on lamps at dusk
21. 21.True or false: to switch on with a clap, use a sound sensor. (a) False (b) True
22. 22.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
23. 23.Which job needs a distance sensor? (a) stop a robot near walls (b) keep an incubator warm (c) water a dry plant (d) close a window in rain
24. 24.🔍 An object is 340 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
25. 25.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
26. 26.🔍 Which sensor would you use to open blinds at sunrise? (a) a temperature sensor (b) a light sensor (c) a gas sensor (d) a rain sensor
27. 27.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
28. 28.Which job needs a rain sensor? (a) warn of a gas leak (b) stop a robot near walls (c) open blinds at sunrise (d) close a window in rain
29. 29.Which job needs a display? (a) show a status light (b) turn to an exact angle (c) open a gate to 90° (d) show the temperature
30. 30.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a display (c) a servo motor (d) a motor
31. 31.🔍 Which sensor would you use to spot someone walking in? (a) a light sensor (b) a distance sensor (c) a motion sensor (d) a sound sensor
32. 32.🔍 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?
33. 33.True or false: to water a dry plant, use a light sensor. (a) True (b) False
34. 34.Which job needs a servo motor? (a) turn to an exact angle (b) beep an alarm (c) show a status light (d) spin a robot’s wheels
35. 35.🔍 Which sensor would you use to stop a robot near walls? (a) a sound sensor (b) a soil moisture sensor (c) a rain sensor (d) a distance sensor
36. 36.🔍 Which sensor would you use to measure classroom noise? (a) a motion sensor (b) a light sensor (c) a rain sensor (d) a sound sensor
37. 37.🔍 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?
38. 38.🔍 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?
39. 39.🔍 Which sensor would you use to water a dry plant? (a) a gas sensor (b) a light sensor (c) a soil moisture sensor (d) a sound sensor
40. 40.Which job needs a buzzer? (a) open a gate to 90° (b) spin a robot’s wheels (c) beep an alarm (d) move water to plants

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