Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 254 · 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.🔍 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)?
3. 3.🔍 Which sensor would you use to start a fan when hot? (a) a motion sensor (b) a distance sensor (c) a light sensor (d) a temperature sensor
4. 4.True or false: to spot someone walking in, use a rain sensor. (a) True (b) False
5. 5.Which job needs a distance sensor? (a) switch on lamps at dusk (b) warn of a gas leak (c) open blinds at sunrise (d) make a parking alarm
6. 6.🔍 Which sensor would you use to spot someone walking in? (a) a rain sensor (b) a motion sensor (c) a gas sensor (d) a sound sensor
7. 7.Which job needs a temperature sensor? (a) keep an incubator warm (b) switch on lamps at dusk (c) make a parking alarm (d) open blinds at sunrise
8. 8.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a power source (c) a fuse (d) an input
9. 9.Which job needs a motor? (a) spin a robot’s wheels (b) show a status light (c) turn to an exact angle (d) move water to plants
10. 10.🔍 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?
11. 11.Which job needs a gas sensor? (a) start a fan when hot (b) switch on with a clap (c) warn of a gas leak (d) make a parking alarm
12. 12.Which job needs a buzzer? (a) beep an alarm (b) move water to plants (c) spin a robot’s wheels (d) open a gate to 90°
13. 13.⚙️ Which actuator would you use to move water to plants? (a) a display (b) an LED (c) a servo motor (d) a pump
14. 14.True or false: to stop a robot near walls, use a distance sensor. (a) True (b) False
15. 15.🔍 Which sensor would you use to water a dry plant? (a) a temperature sensor (b) a light sensor (c) a soil moisture sensor (d) a sound sensor
16. 16.Which job needs a sound sensor? (a) water a dry plant (b) switch on lamps at dusk (c) switch on with a clap (d) start a fan when hot
17. 17.⚙️ What is an actuator? (a) an output that acts (b) a program (c) a sensor (d) a battery
18. 18.⚙️ Which actuator would you use to show a status light? (a) a display (b) an LED (c) a servo motor (d) a motor
19. 19.🔍 An object is 153 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
20. 20.🔍 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)?
21. 21.⚙️ Which actuator would you use to show the temperature? (a) a servo motor (b) a buzzer (c) a pump (d) a display
22. 22.True or false: to start a fan when hot, use a sound sensor. (a) True (b) False
23. 23.⚙️ Which actuator would you use to beep an alarm? (a) a motor (b) a buzzer (c) an LED (d) a servo motor
24. 24.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
25. 25.🔍 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)?
26. 26.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
27. 27.Which job needs a servo motor? (a) spin a robot’s wheels (b) show the temperature (c) beep an alarm (d) turn to an exact angle
28. 28.True or false: to open blinds at sunrise, use a sound sensor. (a) True (b) False
29. 29.⚙️ Which actuator would you use to turn to an exact angle? (a) an LED (b) a servo motor (c) a pump (d) a display
30. 30.True or false: to make a parking alarm, use a temperature sensor. (a) False (b) True
31. 31.🔍 Which sensor would you use to open blinds at sunrise? (a) a sound sensor (b) a light sensor (c) a temperature sensor (d) a gas sensor
32. 32.🔍 Which sensor would you use to switch on with a clap? (a) a gas sensor (b) a temperature sensor (c) a motion sensor (d) a sound sensor
33. 33.🔍 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)?
34. 34.🔍 Which sensor would you use to stop a robot near walls? (a) a motion sensor (b) a distance sensor (c) a temperature sensor (d) a soil moisture sensor
35. 35.🔍 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?
36. 36.🔍 Which sensor would you use to switch on lamps at dusk? (a) a rain sensor (b) a motion sensor (c) a light sensor (d) a temperature sensor
37. 37.⚙️ Which actuator would you use to open a gate to 90°? (a) a servo motor (b) an LED (c) a buzzer (d) a pump
38. 38.Which job needs a rain sensor? (a) measure classroom noise (b) make a parking alarm (c) open blinds at sunrise (d) close a window in rain
39. 39.True or false: to start a fan when hot, use a soil moisture sensor. (a) False (b) True
40. 40.⚙️ Which actuator would you use to spin a robot’s wheels? (a) an LED (b) a motor (c) a pump (d) a servo motor

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