Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 341 · 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.🔍 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?
2. 2.🔍 A distance sensor sends a sound pulse and hears the echo 6 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
3. 3.Which job needs a pump? (a) move water to plants (b) open a gate to 90° (c) spin a robot’s wheels (d) turn to an exact angle
4. 4.🔍 Which sensor would you use to open blinds at sunrise? (a) a temperature sensor (b) a sound sensor (c) a light sensor (d) a distance sensor
5. 5.⚙️ What is an actuator? (a) a program (b) a battery (c) a sensor (d) an output that acts
6. 6.⚙️ Which actuator would you use to show a status light? (a) a display (b) an LED (c) a servo motor (d) a buzzer
7. 7.True or false: to warn of a gas leak, use a gas sensor. (a) True (b) False
8. 8.🔍 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)?
9. 9.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
10. 10.True or false: to close a window in rain, use a distance sensor. (a) False (b) True
11. 11.🔍 A distance sensor sends a sound pulse and hears the echo 10 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
12. 12.🔍 A distance sensor sends a sound pulse and hears the echo 18 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
13. 13.🔍 Which sensor would you use to spot someone walking in? (a) a gas sensor (b) a light sensor (c) a rain sensor (d) a motion sensor
14. 14.True or false: to measure classroom noise, use a sound sensor. (a) True (b) False
15. 15.Which job needs a temperature sensor? (a) stop a robot near walls (b) switch on lamps at dusk (c) open blinds at sunrise (d) start a fan when hot
16. 16.Which job needs a rain sensor? (a) make a parking alarm (b) keep an incubator warm (c) open blinds at sunrise (d) close a window in rain
17. 17.Which job needs a display? (a) open a gate to 90° (b) show the temperature (c) move water to plants (d) spin a robot’s wheels
18. 18.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a display (b) a pump (c) a motor (d) an LED
19. 19.🔍 Which sensor would you use to measure classroom noise? (a) a rain sensor (b) a light sensor (c) a sound sensor (d) a soil moisture sensor
20. 20.🔍 Which sensor would you use to close a window in rain? (a) a temperature sensor (b) a sound sensor (c) a soil moisture sensor (d) a rain sensor
21. 21.⚙️ Which actuator would you use to turn to an exact angle? (a) a buzzer (b) a servo motor (c) an LED (d) a display
22. 22.🔍 A distance sensor sends a sound pulse and hears the echo 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
23. 23.Which job needs a gas sensor? (a) warn of a gas leak (b) open blinds at sunrise (c) close a window in rain (d) switch on lamps at dusk
24. 24.Which job needs a buzzer? (a) move water to plants (b) beep an alarm (c) turn to an exact angle (d) open a gate to 90°
25. 25.🔍 Which sensor would you use to keep an incubator warm? (a) a temperature sensor (b) a sound sensor (c) a soil moisture sensor (d) a distance sensor
26. 26.True or false: to water a dry plant, use a gas sensor. (a) True (b) False
27. 27.🔍 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)?
28. 28.⚙️ Which actuator would you use to open a gate to 90°? (a) a buzzer (b) a servo motor (c) a motor (d) an LED
29. 29.True or false: to warn of a gas leak, use a sound sensor. (a) True (b) False
30. 30.🔍 Which sensor would you use to warn of a gas leak? (a) a soil moisture sensor (b) a gas sensor (c) a sound sensor (d) a light sensor
31. 31.True or false: to start a fan when hot, use a light sensor. (a) False (b) True
32. 32.🔍 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)?
33. 33.Which job needs a soil moisture sensor? (a) stop a robot near walls (b) measure classroom noise (c) keep an incubator warm (d) water a dry plant
34. 34.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
35. 35.🔍 Which sensor would you use to make a parking alarm? (a) a distance sensor (b) a sound sensor (c) a motion sensor (d) a temperature sensor
36. 36.🔍 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)?
37. 37.Which job needs a light sensor? (a) stop a robot near walls (b) switch on lamps at dusk (c) keep an incubator warm (d) start a fan when hot
38. 38.🔍 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?
39. 39.True or false: to make a parking alarm, use a sound sensor. (a) True (b) False
40. 40.🔍 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?

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