Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 258 · 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) switch on lamps at dusk (b) water a dry plant (c) open blinds at sunrise (d) stop a robot near walls
2. 2.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a fuse (c) an input (d) a power source
3. 3.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a light sensor (c) a rain sensor (d) a soil moisture sensor
4. 4.🔍 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)?
5. 5.Which job needs an LED? (a) turn to an exact angle (b) show a status light (c) beep an alarm (d) show the temperature
6. 6.Which job needs a distance sensor? (a) switch on with a clap (b) start a fan when hot (c) make a parking alarm (d) water a dry plant
7. 7.🔍 A distance sensor sends a sound pulse and hears the echo 17 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
8. 8.🔍 Which sensor would you use to make a parking alarm? (a) a distance sensor (b) a rain sensor (c) a temperature sensor (d) a gas sensor
9. 9.⚙️ Which actuator would you use to show a status light? (a) a servo motor (b) a motor (c) an LED (d) a buzzer
10. 10.🔍 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)?
11. 11.Which job needs a distance sensor? (a) warn of a gas leak (b) stop a robot near walls (c) open blinds at sunrise (d) measure classroom noise
12. 12.🔍 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?
13. 13.⚙️ Which actuator would you use to move water to plants? (a) a servo motor (b) a pump (c) a buzzer (d) a motor
14. 14.🔍 Which sensor would you use to keep an incubator warm? (a) a motion sensor (b) a temperature sensor (c) a soil moisture sensor (d) a light sensor
15. 15.🔍 A distance sensor sends a sound pulse and hears the echo 15 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
16. 16.🔍 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?
17. 17.⚙️ What is an actuator? (a) an output that acts (b) a sensor (c) a program (d) a battery
18. 18.🔍 Which sensor would you use to switch on lamps at dusk? (a) a distance sensor (b) a motion sensor (c) a temperature sensor (d) a light sensor
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.🔍 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?
21. 21.🔍 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?
22. 22.🔍 A distance sensor sends a sound pulse and hears the echo 16 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
23. 23.Which job needs a buzzer? (a) spin a robot’s wheels (b) move water to plants (c) beep an alarm (d) show the temperature
24. 24.True or false: to warn of a gas leak, use a temperature sensor. (a) False (b) True
25. 25.True or false: to water a dry plant, use a sound sensor. (a) True (b) False
26. 26.True or false: to stop a robot near walls, use a distance sensor. (a) True (b) False
27. 27.🔍 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?
28. 28.🔍 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?
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.🔍 A distance sensor sends a sound pulse and hears the echo 5 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
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.⚙️ Which actuator would you use to open a gate to 90°? (a) a servo motor (b) a display (c) a pump (d) an LED
33. 33.⚙️ Which actuator would you use to turn to an exact angle? (a) a motor (b) a servo motor (c) an LED (d) a pump
34. 34.Which job needs a sound sensor? (a) switch on lamps at dusk (b) switch on with a clap (c) close a window in rain (d) make a parking alarm
35. 35.Which job needs a light sensor? (a) spot someone walking in (b) stop a robot near walls (c) switch on lamps at dusk (d) warn of a gas leak
36. 36.🔍 Which sensor would you use to spot someone walking in? (a) a rain sensor (b) a temperature sensor (c) a sound sensor (d) a motion sensor
37. 37.Which job needs a motor? (a) open a gate to 90° (b) show a status light (c) spin a robot’s wheels (d) beep an alarm
38. 38.Which job needs a pump? (a) move water to plants (b) spin a robot’s wheels (c) show a status light (d) show the temperature
39. 39.Which job needs a temperature sensor? (a) spot someone walking in (b) warn of a gas leak (c) measure classroom noise (d) start a fan when hot
40. 40.True or false: to start a fan when hot, use a soil moisture sensor. (a) False (b) True

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