Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 135 · 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 an LED? (a) open a gate to 90° (b) turn to an exact angle (c) show a status light (d) beep an alarm
2. 2.Which job needs a display? (a) spin a robot’s wheels (b) show a status light (c) show the temperature (d) beep an alarm
3. 3.🔍 Which sensor would you use to switch on with a clap? (a) a temperature sensor (b) a sound sensor (c) a distance sensor (d) a light sensor
4. 4.🔍 A distance sensor sends a sound pulse and hears the echo 18 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
5. 5.🔍 Which sensor would you use to spot someone walking in? (a) a rain sensor (b) a motion sensor (c) a temperature sensor (d) a distance sensor
6. 6.🔍 An object is 238 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
7. 7.🔍 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)?
8. 8.🔍 An object is 85 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
9. 9.🔍 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)?
10. 10.⚙️ Which actuator would you use to show a status light? (a) a pump (b) an LED (c) a motor (d) a servo motor
11. 11.🔍 Which sensor would you use to start a fan when hot? (a) a gas sensor (b) a soil moisture sensor (c) a temperature sensor (d) a light sensor
12. 12.Which job needs a distance sensor? (a) warn of a gas leak (b) make a parking alarm (c) close a window in rain (d) measure classroom noise
13. 13.⚙️ Which actuator would you use to show the temperature? (a) a buzzer (b) an LED (c) a display (d) a servo motor
14. 14.True or false: to warn of a gas leak, use a gas sensor. (a) False (b) True
15. 15.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
16. 16.True or false: to make a parking alarm, use a light sensor. (a) False (b) True
17. 17.True or false: to switch on lamps at dusk, use a soil moisture sensor. (a) False (b) True
18. 18.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
19. 19.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an output (d) an input
20. 20.🔍 An object is 51 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
21. 21.⚙️ What is an actuator? (a) a sensor (b) a battery (c) an output that acts (d) a program
22. 22.🔍 Which sensor would you use to keep an incubator warm? (a) a temperature sensor (b) a soil moisture sensor (c) a distance sensor (d) a light sensor
23. 23.⚙️ Which actuator would you use to beep an alarm? (a) a motor (b) a pump (c) a servo motor (d) a buzzer
24. 24.True or false: to stop a robot near walls, use a motion sensor. (a) True (b) False
25. 25.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) an LED (c) a servo motor (d) a motor
26. 26.Which job needs a motor? (a) spin a robot’s wheels (b) beep an alarm (c) move water to plants (d) open a gate to 90°
27. 27.Which job needs a light sensor? (a) water a dry plant (b) warn of a gas leak (c) make a parking alarm (d) open blinds at sunrise
28. 28.Which job needs a sound sensor? (a) switch on with a clap (b) spot someone walking in (c) start a fan when hot (d) keep an incubator warm
29. 29.Which job needs a motion sensor? (a) spot someone walking in (b) open blinds at sunrise (c) switch on lamps at dusk (d) keep an incubator warm
30. 30.🔍 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?
31. 31.Which job needs a temperature sensor? (a) measure classroom noise (b) water a dry plant (c) start a fan when hot (d) close a window in rain
32. 32.⚙️ Which actuator would you use to move water to plants? (a) a servo motor (b) an LED (c) a pump (d) a motor
33. 33.Which job needs a temperature sensor? (a) switch on with a clap (b) water a dry plant (c) keep an incubator warm (d) switch on lamps at dusk
34. 34.🔍 Which sensor would you use to switch on lamps at dusk? (a) a distance sensor (b) a light sensor (c) a temperature sensor (d) a soil moisture sensor
35. 35.True or false: to switch on lamps at dusk, use a gas sensor. (a) True (b) False
36. 36.🔍 Which sensor would you use to warn of a gas leak? (a) a soil moisture sensor (b) a light sensor (c) a rain sensor (d) a gas sensor
37. 37.🔍 Which sensor would you use to measure classroom noise? (a) a sound sensor (b) a temperature sensor (c) a soil moisture sensor (d) a motion sensor
38. 38.🔍 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?
39. 39.Which job needs a gas sensor? (a) warn of a gas leak (b) open blinds at sunrise (c) start a fan when hot (d) stop a robot near walls
40. 40.True or false: to switch on lamps at dusk, use a distance sensor. (a) True (b) False

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