Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 81 · 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.🔍 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)?
2. 2.Which job needs a gas sensor? (a) switch on lamps at dusk (b) water a dry plant (c) warn of a gas leak (d) spot someone walking in
3. 3.Which job needs a motor? (a) show a status light (b) turn to an exact angle (c) show the temperature (d) spin a robot’s wheels
4. 4.Which job needs a servo motor? (a) show a status light (b) spin a robot’s wheels (c) turn to an exact angle (d) show the temperature
5. 5.Which job needs a rain sensor? (a) switch on lamps at dusk (b) switch on with a clap (c) close a window in rain (d) open blinds at sunrise
6. 6.True or false: to warn of a gas leak, use a rain sensor. (a) False (b) True
7. 7.🔍 A distance sensor sends a sound pulse and hears the echo 3 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
8. 8.Which job needs a temperature sensor? (a) keep an incubator warm (b) measure classroom noise (c) warn of a gas leak (d) open blinds at sunrise
9. 9.True or false: to start a fan when hot, use a soil moisture sensor. (a) False (b) True
10. 10.⚙️ What is an actuator? (a) an output that acts (b) a battery (c) a sensor (d) a program
11. 11.🔍 Which sensor would you use to measure classroom noise? (a) a rain sensor (b) a light sensor (c) a sound sensor (d) a temperature sensor
12. 12.Which job needs a servo motor? (a) spin a robot’s wheels (b) show a status light (c) open a gate to 90° (d) move water to plants
13. 13.Which job needs a pump? (a) open a gate to 90° (b) move water to plants (c) show a status light (d) spin a robot’s wheels
14. 14.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) a fuse (c) a power source (d) an output
15. 15.True or false: to switch on with a clap, use a light sensor. (a) True (b) False
16. 16.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a pump (c) a motor (d) a servo motor
17. 17.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a pump (c) an LED (d) a servo motor
18. 18.Which job needs a buzzer? (a) show the temperature (b) spin a robot’s wheels (c) turn to an exact angle (d) beep an alarm
19. 19.🔍 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?
20. 20.🔍 Which sensor would you use to warn of a gas leak? (a) a sound sensor (b) a soil moisture sensor (c) a gas sensor (d) a rain sensor
21. 21.🔍 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?
22. 22.🔍 Which sensor would you use to close a window in rain? (a) a gas sensor (b) a motion sensor (c) a rain sensor (d) a temperature sensor
23. 23.🔍 Which sensor would you use to start a fan when hot? (a) a light sensor (b) a soil moisture sensor (c) a sound sensor (d) a temperature sensor
24. 24.Which job needs a light sensor? (a) switch on lamps at dusk (b) make a parking alarm (c) close a window in rain (d) water a dry plant
25. 25.⚙️ Which actuator would you use to show a status light? (a) a pump (b) a buzzer (c) an LED (d) a servo motor
26. 26.🔍 Which sensor would you use to make a parking alarm? (a) a motion sensor (b) a temperature sensor (c) a rain sensor (d) a distance sensor
27. 27.🔍 Which sensor would you use to open blinds at sunrise? (a) a rain sensor (b) a sound sensor (c) a distance sensor (d) a light sensor
28. 28.🔍 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?
29. 29.🔍 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)?
30. 30.🔍 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?
31. 31.⚙️ Which actuator would you use to open a gate to 90°? (a) an LED (b) a pump (c) a servo motor (d) a display
32. 32.🔍 Which sensor would you use to water a dry plant? (a) a rain sensor (b) a soil moisture sensor (c) a gas sensor (d) a light sensor
33. 33.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a pump (b) a servo motor (c) a motor (d) a display
34. 34.⚙️ Which actuator would you use to turn to an exact angle? (a) a display (b) an LED (c) a pump (d) a servo motor
35. 35.Which job needs an LED? (a) beep an alarm (b) spin a robot’s wheels (c) open a gate to 90° (d) show a status light
36. 36.Which job needs a soil moisture sensor? (a) water a dry plant (b) keep an incubator warm (c) measure classroom noise (d) spot someone walking in
37. 37.🔍 An object is 204 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
38. 38.🔍 An object is 187 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
39. 39.True or false: to keep an incubator warm, use a motion sensor. (a) True (b) False
40. 40.🔍 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)?

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