Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 235 · 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 soil moisture sensor? (a) close a window in rain (b) water a dry plant (c) spot someone walking in (d) warn of a gas leak
2. 2.⚙️ What is an actuator? (a) a sensor (b) a battery (c) an output that acts (d) a program
3. 3.Which job needs a gas sensor? (a) open blinds at sunrise (b) warn of a gas leak (c) measure classroom noise (d) keep an incubator warm
4. 4.⚙️ Which actuator would you use to turn to an exact angle? (a) a buzzer (b) a motor (c) a servo motor (d) a display
5. 5.🔍 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
6. 6.⚙️ Which actuator would you use to show a status light? (a) a servo motor (b) a buzzer (c) an LED (d) a motor
7. 7.Which job needs a temperature sensor? (a) keep an incubator warm (b) open blinds at sunrise (c) water a dry plant (d) measure classroom noise
8. 8.Which job needs a buzzer? (a) open a gate to 90° (b) show the temperature (c) turn to an exact angle (d) beep an alarm
9. 9.🔍 A distance sensor sends a sound pulse and hears the echo 11 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
10. 10.🔍 Which sensor would you use to water a dry plant? (a) a sound sensor (b) a temperature sensor (c) a light sensor (d) a soil moisture sensor
11. 11.True or false: to make a parking alarm, use a distance sensor. (a) True (b) False
12. 12.🔍 Which sensor would you use to stop a robot near walls? (a) a light sensor (b) a rain sensor (c) a distance sensor (d) a temperature sensor
13. 13.🔍 Which sensor would you use to keep an incubator warm? (a) a rain sensor (b) a gas sensor (c) a sound sensor (d) a temperature sensor
14. 14.🔍 Which sensor would you use to start a fan when hot? (a) a rain sensor (b) a temperature sensor (c) a sound sensor (d) a soil moisture sensor
15. 15.Which job needs a temperature sensor? (a) stop a robot near walls (b) start a fan when hot (c) measure classroom noise (d) spot someone walking in
16. 16.Which job needs a light sensor? (a) keep an incubator warm (b) switch on lamps at dusk (c) warn of a gas leak (d) make a parking alarm
17. 17.🔍 An object is 255 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
18. 18.🔍 Which sensor would you use to warn of a gas leak? (a) a gas sensor (b) a distance sensor (c) a soil moisture sensor (d) a light sensor
19. 19.Which job needs a servo motor? (a) open a gate to 90° (b) spin a robot’s wheels (c) beep an alarm (d) move water to plants
20. 20.True or false: to keep an incubator warm, use a sound sensor. (a) True (b) False
21. 21.Which job needs an LED? (a) open a gate to 90° (b) show the temperature (c) spin a robot’s wheels (d) show a status light
22. 22.Which job needs a servo motor? (a) move water to plants (b) spin a robot’s wheels (c) turn to an exact angle (d) beep an alarm
23. 23.Which job needs a rain sensor? (a) switch on lamps at dusk (b) start a fan when hot (c) close a window in rain (d) water a dry plant
24. 24.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a power source (c) a fuse (d) an input
25. 25.Which job needs a motion sensor? (a) switch on with a clap (b) spot someone walking in (c) open blinds at sunrise (d) warn of a gas leak
26. 26.Which job needs a display? (a) turn to an exact angle (b) move water to plants (c) show the temperature (d) open a gate to 90°
27. 27.🔍 Which sensor would you use to open blinds at sunrise? (a) a light sensor (b) a gas sensor (c) a distance sensor (d) a temperature sensor
28. 28.Which job needs a sound sensor? (a) switch on with a clap (b) open blinds at sunrise (c) warn of a gas leak (d) stop a robot near walls
29. 29.⚙️ Which actuator would you use to open a gate to 90°? (a) a pump (b) a buzzer (c) a servo motor (d) a motor
30. 30.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) an LED (c) a pump (d) a motor
31. 31.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
32. 32.🔍 Which sensor would you use to make a parking alarm? (a) a gas sensor (b) a rain sensor (c) a distance sensor (d) a light sensor
33. 33.True or false: to switch on with a clap, use a soil moisture sensor. (a) True (b) False
34. 34.🔍 Which sensor would you use to switch on lamps at dusk? (a) a temperature sensor (b) a distance sensor (c) a sound sensor (d) a light sensor
35. 35.🔍 An object is 289 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
36. 36.🔍 Which sensor would you use to measure classroom noise? (a) a gas sensor (b) a temperature sensor (c) a light sensor (d) a sound sensor
37. 37.Which job needs a motor? (a) turn to an exact angle (b) move water to plants (c) open a gate to 90° (d) spin a robot’s wheels
38. 38.🔍 A distance sensor sends a sound pulse and hears the echo 4 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
39. 39.True or false: to stop a robot near walls, use a light sensor. (a) True (b) False
40. 40.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a display (b) an LED (c) a buzzer (d) a motor

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