Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 212 · 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 sound sensor? (a) close a window in rain (b) switch on with a clap (c) keep an incubator warm (d) make a parking alarm
2. 2.🔍 Which sensor would you use to spot someone walking in? (a) a temperature sensor (b) a light sensor (c) a gas sensor (d) a motion sensor
3. 3.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a pump (b) a display (c) a buzzer (d) a motor
4. 4.🔍 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)?
5. 5.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) a fuse (c) a power source (d) an output
6. 6.🔍 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)?
7. 7.Which job needs a pump? (a) spin a robot’s wheels (b) show a status light (c) open a gate to 90° (d) move water to plants
8. 8.⚙️ Which actuator would you use to move water to plants? (a) a pump (b) a servo motor (c) an LED (d) a motor
9. 9.Which job needs a temperature sensor? (a) start a fan when hot (b) measure classroom noise (c) make a parking alarm (d) switch on with a clap
10. 10.🔍 Which sensor would you use to stop a robot near walls? (a) a motion sensor (b) a distance sensor (c) a sound sensor (d) a gas sensor
11. 11.🔍 Which sensor would you use to water a dry plant? (a) a motion sensor (b) a light sensor (c) a soil moisture sensor (d) a distance sensor
12. 12.Which job needs a display? (a) show the temperature (b) spin a robot’s wheels (c) turn to an exact angle (d) open a gate to 90°
13. 13.Which job needs a motion sensor? (a) spot someone walking in (b) make a parking alarm (c) open blinds at sunrise (d) start a fan when hot
14. 14.🔍 Which sensor would you use to switch on with a clap? (a) a gas sensor (b) a sound sensor (c) a temperature sensor (d) a rain sensor
15. 15.🔍 Which sensor would you use to start a fan when hot? (a) a distance sensor (b) a temperature sensor (c) a gas sensor (d) a light sensor
16. 16.Which job needs a distance sensor? (a) warn of a gas leak (b) spot someone walking in (c) switch on lamps at dusk (d) stop a robot near walls
17. 17.True or false: to switch on lamps at dusk, use a distance sensor. (a) False (b) True
18. 18.Which job needs a soil moisture sensor? (a) start a fan when hot (b) warn of a gas leak (c) water a dry plant (d) close a window in rain
19. 19.True or false: to open blinds at sunrise, use a light sensor. (a) True (b) False
20. 20.⚙️ What is an actuator? (a) a battery (b) a program (c) a sensor (d) an output that acts
21. 21.Which job needs an LED? (a) show a status light (b) open a gate to 90° (c) spin a robot’s wheels (d) beep an alarm
22. 22.Which job needs a servo motor? (a) open a gate to 90° (b) show the temperature (c) show a status light (d) spin a robot’s wheels
23. 23.🔍 Which sensor would you use to switch on lamps at dusk? (a) a light sensor (b) a motion sensor (c) a distance sensor (d) a temperature sensor
24. 24.Which job needs a light sensor? (a) warn of a gas leak (b) spot someone walking in (c) open blinds at sunrise (d) measure classroom noise
25. 25.🔍 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)?
26. 26.⚙️ Which actuator would you use to show a status light? (a) a buzzer (b) a display (c) an LED (d) a servo motor
27. 27.🔍 An object is 272 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
28. 28.True or false: to stop a robot near walls, use a light sensor. (a) True (b) False
29. 29.True or false: to water a dry plant, use a gas sensor. (a) True (b) False
30. 30.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
31. 31.Which job needs a buzzer? (a) move water to plants (b) spin a robot’s wheels (c) open a gate to 90° (d) beep an alarm
32. 32.🔍 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?
33. 33.Which job needs a light sensor? (a) spot someone walking in (b) measure classroom noise (c) switch on lamps at dusk (d) keep an incubator warm
34. 34.🔍 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?
35. 35.Which job needs a servo motor? (a) show a status light (b) spin a robot’s wheels (c) beep an alarm (d) turn to an exact angle
36. 36.🔍 Which sensor would you use to measure classroom noise? (a) a temperature sensor (b) a soil moisture sensor (c) a distance sensor (d) a sound sensor
37. 37.🔍 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)?
38. 38.Which job needs a gas sensor? (a) switch on lamps at dusk (b) spot someone walking in (c) warn of a gas leak (d) open blinds at sunrise
39. 39.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a pump (c) a buzzer (d) an LED
40. 40.⚙️ Which actuator would you use to open a gate to 90°? (a) a buzzer (b) a servo motor (c) a pump (d) a motor

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