Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 155 · 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.True or false: to water a dry plant, use a soil moisture sensor. (a) False (b) True
2. 2.🔍 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?
3. 3.⚙️ Which actuator would you use to turn to an exact angle? (a) a motor (b) a buzzer (c) an LED (d) a servo motor
4. 4.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a motor (c) a display (d) a pump
5. 5.Which job needs a pump? (a) beep an alarm (b) move water to plants (c) open a gate to 90° (d) show a status light
6. 6.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) an output (c) a power source (d) a fuse
7. 7.Which job needs a gas sensor? (a) water a dry plant (b) warn of a gas leak (c) keep an incubator warm (d) spot someone walking in
8. 8.🔍 Which sensor would you use to make a parking alarm? (a) a motion sensor (b) a light sensor (c) a gas sensor (d) a distance sensor
9. 9.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a pump (c) a motor (d) an LED
10. 10.Which job needs a light sensor? (a) switch on lamps at dusk (b) start a fan when hot (c) close a window in rain (d) measure classroom noise
11. 11.🔍 Which sensor would you use to switch on lamps at dusk? (a) a soil moisture sensor (b) a motion sensor (c) a distance sensor (d) a light sensor
12. 12.🔍 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?
13. 13.🔍 An object is 68 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
14. 14.🔍 Which sensor would you use to open blinds at sunrise? (a) a light sensor (b) a distance sensor (c) a temperature sensor (d) a sound sensor
15. 15.🔍 A distance sensor sends a sound pulse and hears the echo 2 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
16. 16.⚙️ What is an actuator? (a) a battery (b) an output that acts (c) a sensor (d) a program
17. 17.Which job needs a display? (a) show the temperature (b) move water to plants (c) spin a robot’s wheels (d) beep an alarm
18. 18.🔍 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?
19. 19.🔍 A distance sensor sends a sound pulse and hears the echo 13 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
20. 20.True or false: to open blinds at sunrise, use a gas sensor. (a) True (b) False
21. 21.Which job needs a motor? (a) move water to plants (b) open a gate to 90° (c) spin a robot’s wheels (d) show a status light
22. 22.🔍 Which sensor would you use to keep an incubator warm? (a) a temperature sensor (b) a distance sensor (c) a soil moisture sensor (d) a light sensor
23. 23.Which job needs a rain sensor? (a) warn of a gas leak (b) close a window in rain (c) spot someone walking in (d) water a dry plant
24. 24.🔍 An object is 340 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
25. 25.Which job needs a servo motor? (a) show a status light (b) open a gate to 90° (c) beep an alarm (d) spin a robot’s wheels
26. 26.Which job needs a light sensor? (a) measure classroom noise (b) water a dry plant (c) make a parking alarm (d) open blinds at sunrise
27. 27.Which job needs a motion sensor? (a) open blinds at sunrise (b) spot someone walking in (c) stop a robot near walls (d) switch on lamps at dusk
28. 28.Which job needs a soil moisture sensor? (a) water a dry plant (b) stop a robot near walls (c) spot someone walking in (d) warn of a gas leak
29. 29.Which job needs an LED? (a) show the temperature (b) turn to an exact angle (c) spin a robot’s wheels (d) show a status light
30. 30.Which job needs a distance sensor? (a) water a dry plant (b) measure classroom noise (c) make a parking alarm (d) switch on lamps at dusk
31. 31.🔍 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)?
32. 32.🔍 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?
33. 33.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a servo motor (b) a pump (c) a display (d) a motor
34. 34.Which job needs a sound sensor? (a) spot someone walking in (b) measure classroom noise (c) switch on lamps at dusk (d) start a fan when hot
35. 35.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a sound sensor (c) a rain sensor (d) a soil moisture sensor
36. 36.True or false: to open blinds at sunrise, use a light sensor. (a) True (b) False
37. 37.🔍 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?
38. 38.True or false: to measure classroom noise, use a gas sensor. (a) True (b) False
39. 39.True or false: to spot someone walking in, use a motion sensor. (a) True (b) False
40. 40.⚙️ Which actuator would you use to show the temperature? (a) a motor (b) an LED (c) a display (d) a pump

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