Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 199 · 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 306 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
2. 2.True or false: to warn of a gas leak, use a temperature sensor. (a) False (b) True
3. 3.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
4. 4.Which job needs a buzzer? (a) show a status light (b) turn to an exact angle (c) beep an alarm (d) move water to plants
5. 5.⚙️ What is an actuator? (a) a program (b) a sensor (c) a battery (d) an output that acts
6. 6.Which job needs a light sensor? (a) start a fan when hot (b) make a parking alarm (c) open blinds at sunrise (d) close a window in rain
7. 7.⚙️ Which actuator would you use to show the temperature? (a) a buzzer (b) a pump (c) an LED (d) a display
8. 8.🔍 Which sensor would you use to switch on with a clap? (a) a motion sensor (b) a distance sensor (c) a sound sensor (d) a soil moisture sensor
9. 9.🔍 Which sensor would you use to close a window in rain? (a) a motion sensor (b) a light sensor (c) a rain sensor (d) a distance sensor
10. 10.Which job needs a motor? (a) move water to plants (b) spin a robot’s wheels (c) turn to an exact angle (d) beep an alarm
11. 11.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
12. 12.🔍 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)?
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 spot someone walking in? (a) a light sensor (b) a soil moisture sensor (c) a rain sensor (d) a motion sensor
15. 15.Which job needs a gas sensor? (a) keep an incubator warm (b) warn of a gas leak (c) stop a robot near walls (d) close a window in rain
16. 16.🔍 A distance sensor sends a sound pulse and hears the echo 11 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
17. 17.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an output (c) an input (d) a fuse
18. 18.⚙️ Which actuator would you use to beep an alarm? (a) a servo motor (b) a motor (c) a buzzer (d) an LED
19. 19.🔍 Which sensor would you use to open blinds at sunrise? (a) a sound sensor (b) a rain sensor (c) a light sensor (d) a distance sensor
20. 20.Which job needs a rain sensor? (a) close a window in rain (b) make a parking alarm (c) open blinds at sunrise (d) measure classroom noise
21. 21.🔍 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?
22. 22.Which job needs a temperature sensor? (a) measure classroom noise (b) warn of a gas leak (c) water a dry plant (d) start a fan when hot
23. 23.True or false: to switch on with a clap, use a sound sensor. (a) False (b) True
24. 24.Which job needs a display? (a) move water to plants (b) show the temperature (c) spin a robot’s wheels (d) show a status light
25. 25.🔍 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)?
26. 26.True or false: to stop a robot near walls, use a light sensor. (a) True (b) False
27. 27.🔍 A distance sensor sends a sound pulse and hears the echo 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
28. 28.🔍 Which sensor would you use to warn of a gas leak? (a) a soil moisture sensor (b) a temperature sensor (c) a gas sensor (d) a rain sensor
29. 29.🔍 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?
30. 30.Which job needs a sound sensor? (a) water a dry plant (b) switch on with a clap (c) switch on lamps at dusk (d) make a parking alarm
31. 31.Which job needs a temperature sensor? (a) close a window in rain (b) make a parking alarm (c) keep an incubator warm (d) open blinds at sunrise
32. 32.True or false: to warn of a gas leak, use a rain sensor. (a) True (b) False
33. 33.Which job needs an LED? (a) open a gate to 90° (b) show a status light (c) spin a robot’s wheels (d) beep an alarm
34. 34.🔍 Which sensor would you use to make a parking alarm? (a) a distance sensor (b) a light sensor (c) a motion sensor (d) a rain sensor
35. 35.🔍 Which sensor would you use to switch on lamps at dusk? (a) a gas sensor (b) a distance sensor (c) a light sensor (d) a temperature sensor
36. 36.🔍 Which sensor would you use to water a dry plant? (a) a motion sensor (b) a light sensor (c) a rain sensor (d) a soil moisture sensor
37. 37.Which job needs a light sensor? (a) switch on lamps at dusk (b) keep an incubator warm (c) spot someone walking in (d) switch on with a clap
38. 38.⚙️ Which actuator would you use to turn to an exact angle? (a) a servo motor (b) a display (c) a motor (d) an LED
39. 39.Which job needs a motion sensor? (a) water a dry plant (b) stop a robot near walls (c) switch on lamps at dusk (d) spot someone walking in
40. 40.Which job needs a distance sensor? (a) open blinds at sunrise (b) stop a robot near walls (c) close a window in rain (d) switch on with a clap

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