Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 225 · 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 sensor would you use to start a fan when hot? (a) a temperature sensor (b) a rain sensor (c) a sound sensor (d) a motion sensor
2. 2.Which job needs a gas sensor? (a) open blinds at sunrise (b) switch on with a clap (c) warn of a gas leak (d) keep an incubator warm
3. 3.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a pump (c) a servo motor (d) a buzzer
4. 4.⚙️ Which actuator would you use to open a gate to 90°? (a) a servo motor (b) a pump (c) a motor (d) a display
5. 5.True or false: to make a parking alarm, use a temperature sensor. (a) True (b) False
6. 6.🔍 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?
7. 7.⚙️ Which actuator would you use to beep an alarm? (a) an LED (b) a motor (c) a buzzer (d) a display
8. 8.🔍 Which sensor would you use to spot someone walking in? (a) a motion sensor (b) a temperature sensor (c) a distance sensor (d) a gas sensor
9. 9.Which job needs a sound sensor? (a) close a window in rain (b) measure classroom noise (c) stop a robot near walls (d) water a dry plant
10. 10.⚙️ Which actuator would you use to spin a robot’s wheels? (a) an LED (b) a servo motor (c) a motor (d) a buzzer
11. 11.⚙️ What is an actuator? (a) a program (b) an output that acts (c) a battery (d) a sensor
12. 12.🔍 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?
13. 13.Which job needs a soil moisture sensor? (a) close a window in rain (b) water a dry plant (c) stop a robot near walls (d) start a fan when hot
14. 14.Which job needs a pump? (a) turn to an exact angle (b) beep an alarm (c) spin a robot’s wheels (d) move water to plants
15. 15.Which job needs a sound sensor? (a) stop a robot near walls (b) water a dry plant (c) switch on lamps at dusk (d) switch on with a clap
16. 16.🔍 Which sensor would you use to make a parking alarm? (a) a soil moisture sensor (b) a light sensor (c) a distance sensor (d) a rain sensor
17. 17.🔍 Which sensor would you use to keep an incubator warm? (a) a motion sensor (b) a soil moisture sensor (c) a temperature sensor (d) a gas sensor
18. 18.Which job needs a motor? (a) move water to plants (b) show the temperature (c) spin a robot’s wheels (d) turn to an exact angle
19. 19.🔍 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)?
20. 20.🔍 Which sensor would you use to open blinds at sunrise? (a) a temperature sensor (b) a distance sensor (c) a light sensor (d) a rain sensor
21. 21.Which job needs an LED? (a) move water to plants (b) beep an alarm (c) turn to an exact angle (d) show a status light
22. 22.Which job needs a temperature sensor? (a) warn of a gas leak (b) water a dry plant (c) start a fan when hot (d) switch on with a clap
23. 23.Which job needs a rain sensor? (a) warn of a gas leak (b) open blinds at sunrise (c) make a parking alarm (d) close a window in rain
24. 24.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a power source (c) an input (d) a fuse
25. 25.True or false: to stop a robot near walls, use a motion sensor. (a) True (b) False
26. 26.⚙️ Which actuator would you use to show a status light? (a) an LED (b) a display (c) a servo motor (d) a pump
27. 27.Which job needs a servo motor? (a) show the temperature (b) spin a robot’s wheels (c) turn to an exact angle (d) show a status light
28. 28.🔍 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)?
29. 29.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
30. 30.🔍 Which sensor would you use to measure classroom noise? (a) a rain sensor (b) a distance sensor (c) a sound sensor (d) a light sensor
31. 31.🔍 A distance sensor sends a sound pulse and hears the echo 8 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
32. 32.True or false: to make a parking alarm, use a distance sensor. (a) True (b) False
33. 33.Which job needs a light sensor? (a) make a parking alarm (b) keep an incubator warm (c) switch on lamps at dusk (d) water a dry plant
34. 34.True or false: to measure classroom noise, use a distance sensor. (a) True (b) False
35. 35.True or false: to switch on with a clap, use a soil moisture sensor. (a) False (b) True
36. 36.True or false: to stop a robot near walls, use a light sensor. (a) True (b) False
37. 37.Which job needs a motion sensor? (a) stop a robot near walls (b) keep an incubator warm (c) start a fan when hot (d) spot someone walking in
38. 38.🔍 A distance sensor sends a sound pulse and hears the echo 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
39. 39.⚙️ Which actuator would you use to move water to plants? (a) an LED (b) a buzzer (c) a pump (d) a display
40. 40.🔍 Which sensor would you use to switch on with a clap? (a) a motion sensor (b) a light sensor (c) a sound sensor (d) a temperature sensor

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