Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 192 · 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 3 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
2. 2.True or false: to start a fan when hot, use a gas sensor. (a) True (b) False
3. 3.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
4. 4.Which job needs a gas sensor? (a) warn of a gas leak (b) make a parking alarm (c) measure classroom noise (d) spot someone walking in
5. 5.True or false: to stop a robot near walls, use a distance sensor. (a) True (b) False
6. 6.🔍 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)?
7. 7.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a pump (b) a motor (c) a buzzer (d) a servo motor
8. 8.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a light sensor (c) a sound sensor (d) a soil moisture sensor
9. 9.Which job needs a buzzer? (a) move water to plants (b) beep an alarm (c) open a gate to 90° (d) show a status light
10. 10.🔍 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?
11. 11.⚙️ What is an actuator? (a) an output that acts (b) a program (c) a battery (d) a sensor
12. 12.True or false: to warn of a gas leak, use a soil moisture sensor. (a) False (b) True
13. 13.True or false: to warn of a gas leak, use a gas sensor. (a) True (b) False
14. 14.True or false: to open blinds at sunrise, use a motion sensor. (a) True (b) False
15. 15.🔍 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)?
16. 16.Which job needs a display? (a) spin a robot’s wheels (b) show a status light (c) beep an alarm (d) show the temperature
17. 17.🔍 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?
18. 18.🔍 Which sensor would you use to switch on with a clap? (a) a gas sensor (b) a temperature sensor (c) a light sensor (d) a sound sensor
19. 19.🔍 Which sensor would you use to keep an incubator warm? (a) a light sensor (b) a motion sensor (c) a gas sensor (d) a temperature sensor
20. 20.🔍 Which sensor would you use to warn of a gas leak? (a) a light sensor (b) a sound sensor (c) a gas sensor (d) a motion sensor
21. 21.True or false: to close a window in rain, use a distance sensor. (a) True (b) False
22. 22.🔍 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?
23. 23.⚙️ Which actuator would you use to move water to plants? (a) a display (b) a servo motor (c) a pump (d) a buzzer
24. 24.🔍 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?
25. 25.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) an input (c) a power source (d) an output
26. 26.🔍 Which sensor would you use to measure classroom noise? (a) a distance sensor (b) a motion sensor (c) a temperature sensor (d) a sound sensor
27. 27.Which job needs a servo motor? (a) beep an alarm (b) show a status light (c) turn to an exact angle (d) spin a robot’s wheels
28. 28.Which job needs a soil moisture sensor? (a) switch on lamps at dusk (b) water a dry plant (c) warn of a gas leak (d) close a window in rain
29. 29.🔍 Which sensor would you use to water a dry plant? (a) a rain sensor (b) a gas sensor (c) a soil moisture sensor (d) a light sensor
30. 30.True or false: to switch on lamps at dusk, use a sound sensor. (a) True (b) False
31. 31.True or false: to switch on lamps at dusk, use a temperature sensor. (a) True (b) False
32. 32.🔍 Which sensor would you use to switch on lamps at dusk? (a) a soil moisture sensor (b) a gas sensor (c) a rain sensor (d) a light 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.True or false: to open blinds at sunrise, use a light sensor. (a) True (b) False
35. 35.Which job needs a temperature sensor? (a) start a fan when hot (b) open blinds at sunrise (c) make a parking alarm (d) spot someone walking in
36. 36.🔍 Which sensor would you use to make a parking alarm? (a) a sound sensor (b) a distance sensor (c) a soil moisture sensor (d) a gas sensor
37. 37.🔍 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)?
38. 38.Which job needs a light sensor? (a) make a parking alarm (b) measure classroom noise (c) switch on lamps at dusk (d) warn of a gas leak
39. 39.⚙️ Which actuator would you use to beep an alarm? (a) a display (b) a buzzer (c) a motor (d) a servo motor
40. 40.True or false: to keep an incubator warm, use a light sensor. (a) False (b) True

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