Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 123 · 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 motor? (a) beep an alarm (b) spin a robot’s wheels (c) turn to an exact angle (d) move water to plants
2. 2.Which job needs an LED? (a) beep an alarm (b) open a gate to 90° (c) show a status light (d) show the temperature
3. 3.🔍 Which sensor would you use to open blinds at sunrise? (a) a distance sensor (b) a soil moisture sensor (c) a motion sensor (d) a light sensor
4. 4.Which job needs a motion sensor? (a) close a window in rain (b) stop a robot near walls (c) spot someone walking in (d) start a fan when hot
5. 5.Which job needs a gas sensor? (a) stop a robot near walls (b) warn of a gas leak (c) start a fan when hot (d) close a window in rain
6. 6.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an input (d) an output
7. 7.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
8. 8.True or false: to switch on with a clap, use a soil moisture sensor. (a) True (b) False
9. 9.Which job needs a buzzer? (a) show the temperature (b) show a status light (c) open a gate to 90° (d) beep an alarm
10. 10.🔍 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)?
11. 11.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a pump (b) a display (c) a buzzer (d) a motor
12. 12.⚙️ Which actuator would you use to move water to plants? (a) a pump (b) a servo motor (c) a motor (d) an LED
13. 13.⚙️ Which actuator would you use to open a gate to 90°? (a) a buzzer (b) a display (c) a motor (d) a servo motor
14. 14.🔍 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)?
15. 15.🔍 Which sensor would you use to water a dry plant? (a) a light sensor (b) a soil moisture sensor (c) a temperature sensor (d) a distance sensor
16. 16.🔍 A distance sensor sends a sound pulse and hears the echo 14 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
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.Which job needs a rain sensor? (a) start a fan when hot (b) water a dry plant (c) close a window in rain (d) switch on lamps at dusk
19. 19.🔍 An object is 323 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
20. 20.🔍 Which sensor would you use to warn of a gas leak? (a) a light sensor (b) a soil moisture sensor (c) a rain sensor (d) a gas sensor
21. 21.🔍 Which sensor would you use to start a fan when hot? (a) a rain sensor (b) a light sensor (c) a temperature sensor (d) a motion sensor
22. 22.🔍 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?
23. 23.🔍 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?
24. 24.Which job needs a servo motor? (a) show the temperature (b) move water to plants (c) spin a robot’s wheels (d) turn to an exact angle
25. 25.True or false: to switch on lamps at dusk, use a soil moisture sensor. (a) False (b) True
26. 26.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
27. 27.Which job needs a temperature sensor? (a) make a parking alarm (b) close a window in rain (c) switch on lamps at dusk (d) start a fan when hot
28. 28.⚙️ Which actuator would you use to turn to an exact angle? (a) a display (b) a motor (c) a servo motor (d) a pump
29. 29.Which job needs a light sensor? (a) measure classroom noise (b) make a parking alarm (c) close a window in rain (d) switch on lamps at dusk
30. 30.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
31. 31.True or false: to spot someone walking in, use a light sensor. (a) False (b) True
32. 32.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a pump (c) a servo motor (d) a buzzer
33. 33.🔍 Which sensor would you use to make a parking alarm? (a) a rain sensor (b) a distance sensor (c) a light sensor (d) a sound sensor
34. 34.🔍 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)?
35. 35.True or false: to stop a robot near walls, use a temperature sensor. (a) False (b) True
36. 36.🔍 An object is 34 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
37. 37.🔍 Which sensor would you use to measure classroom noise? (a) a gas sensor (b) a light sensor (c) a rain sensor (d) a sound sensor
38. 38.⚙️ What is an actuator? (a) a sensor (b) a program (c) an output that acts (d) a battery
39. 39.🔍 Which sensor would you use to switch on with a clap? (a) a light sensor (b) a soil moisture sensor (c) a sound sensor (d) a rain sensor
40. 40.True or false: to keep an incubator warm, use a gas sensor. (a) True (b) False

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