Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 184 · 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 13 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
2. 2.Which job needs a motion sensor? (a) make a parking alarm (b) keep an incubator warm (c) stop a robot near walls (d) spot someone walking in
3. 3.🔍 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?
4. 4.Which job needs a temperature sensor? (a) warn of a gas leak (b) switch on lamps at dusk (c) measure classroom noise (d) start a fan when hot
5. 5.Which job needs a display? (a) show the temperature (b) show a status light (c) move water to plants (d) spin a robot’s wheels
6. 6.Which job needs a servo motor? (a) turn to an exact angle (b) spin a robot’s wheels (c) show the temperature (d) move water to plants
7. 7.Which job needs a temperature sensor? (a) measure classroom noise (b) keep an incubator warm (c) spot someone walking in (d) switch on with a clap
8. 8.⚙️ Which actuator would you use to show a status light? (a) an LED (b) a servo motor (c) a pump (d) a display
9. 9.🔍 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?
10. 10.🔍 Which sensor would you use to stop a robot near walls? (a) a light sensor (b) a motion sensor (c) a distance sensor (d) a temperature sensor
11. 11.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
12. 12.Which job needs a soil moisture sensor? (a) measure classroom noise (b) warn of a gas leak (c) water a dry plant (d) make a parking alarm
13. 13.⚙️ What is an actuator? (a) a battery (b) an output that acts (c) a sensor (d) a program
14. 14.Which job needs a rain sensor? (a) make a parking alarm (b) switch on lamps at dusk (c) close a window in rain (d) open blinds at sunrise
15. 15.🔍 Which sensor would you use to switch on with a clap? (a) a motion sensor (b) a gas sensor (c) a sound sensor (d) a soil moisture sensor
16. 16.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a motor (c) an LED (d) a pump
17. 17.True or false: to water a dry plant, use a soil moisture sensor. (a) False (b) True
18. 18.🔍 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)?
19. 19.🔍 Which sensor would you use to start a fan when hot? (a) a temperature sensor (b) a distance sensor (c) a light sensor (d) a gas sensor
20. 20.Which job needs a sound sensor? (a) measure classroom noise (b) stop a robot near walls (c) start a fan when hot (d) open blinds at sunrise
21. 21.🔍 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?
22. 22.Which job needs a motor? (a) open a gate to 90° (b) show the temperature (c) spin a robot’s wheels (d) show a status light
23. 23.🔍 Which sensor would you use to make a parking alarm? (a) a light sensor (b) a distance sensor (c) a temperature sensor (d) a soil moisture sensor
24. 24.🔍 Which sensor would you use to switch on lamps at dusk? (a) a motion sensor (b) a distance sensor (c) a light sensor (d) a sound sensor
25. 25.Which job needs a pump? (a) open a gate to 90° (b) move water to plants (c) show the temperature (d) show a status light
26. 26.🔍 A distance sensor sends a sound pulse and hears the echo 1 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
27. 27.Which job needs a light sensor? (a) stop a robot near walls (b) warn of a gas leak (c) keep an incubator warm (d) open blinds at sunrise
28. 28.🔍 Which sensor would you use to warn of a gas leak? (a) a distance sensor (b) a gas sensor (c) a rain sensor (d) a temperature sensor
29. 29.⚙️ Which actuator would you use to show the temperature? (a) a pump (b) a display (c) a buzzer (d) a servo motor
30. 30.Which job needs a distance sensor? (a) switch on lamps at dusk (b) close a window in rain (c) warn of a gas leak (d) make a parking alarm
31. 31.🔍 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)?
32. 32.🔍 Which sensor would you use to measure classroom noise? (a) a temperature sensor (b) a light sensor (c) a sound sensor (d) a distance sensor
33. 33.🔍 Which sensor would you use to spot someone walking in? (a) a temperature sensor (b) a soil moisture sensor (c) a motion sensor (d) a gas sensor
34. 34.Which job needs a buzzer? (a) move water to plants (b) beep an alarm (c) show the temperature (d) open a gate to 90°
35. 35.Which job needs a sound sensor? (a) switch on lamps at dusk (b) keep an incubator warm (c) switch on with a clap (d) start a fan when hot
36. 36.True or false: to close a window in rain, use a distance sensor. (a) True (b) False
37. 37.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a servo motor (c) a pump (d) a motor
38. 38.True or false: to warn of a gas leak, use a sound sensor. (a) False (b) True
39. 39.🔍 Which sensor would you use to keep an incubator warm? (a) a soil moisture sensor (b) a temperature sensor (c) a distance sensor (d) a sound sensor
40. 40.Which job needs a distance sensor? (a) keep an incubator warm (b) stop a robot near walls (c) close a window in rain (d) switch on with a clap

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