Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 55 · 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.Which job needs a light sensor? (a) warn of a gas leak (b) switch on with a clap (c) stop a robot near walls (d) switch on lamps at dusk
2. 2.🔍 Which sensor would you use to water a dry plant? (a) a distance sensor (b) a gas sensor (c) a soil moisture sensor (d) a light sensor
3. 3.🔍 Which sensor would you use to switch on with a clap? (a) a gas sensor (b) a motion sensor (c) a soil moisture sensor (d) a sound sensor
4. 4.🔍 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)?
5. 5.⚙️ Which actuator would you use to show the temperature? (a) a buzzer (b) a pump (c) a display (d) an LED
6. 6.🔍 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?
7. 7.🔍 Which sensor would you use to warn of a gas leak? (a) a rain sensor (b) a gas sensor (c) a soil moisture sensor (d) a light sensor
8. 8.🔍 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?
9. 9.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
10. 10.Which job needs a rain sensor? (a) switch on lamps at dusk (b) measure classroom noise (c) close a window in rain (d) water a dry plant
11. 11.⚙️ What is an actuator? (a) a program (b) an output that acts (c) a sensor (d) a battery
12. 12.Which job needs a distance sensor? (a) close a window in rain (b) stop a robot near walls (c) switch on lamps at dusk (d) measure classroom noise
13. 13.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
14. 14.True or false: to close a window in rain, use a light sensor. (a) False (b) True
15. 15.Which job needs a soil moisture sensor? (a) stop a robot near walls (b) switch on lamps at dusk (c) make a parking alarm (d) water a dry plant
16. 16.True or false: to spot someone walking in, use a motion sensor. (a) True (b) False
17. 17.Which job needs a temperature sensor? (a) measure classroom noise (b) switch on lamps at dusk (c) warn of a gas leak (d) start a fan when hot
18. 18.Which job needs a servo motor? (a) beep an alarm (b) open a gate to 90° (c) move water to plants (d) show the temperature
19. 19.Which job needs a light sensor? (a) open blinds at sunrise (b) measure classroom noise (c) close a window in rain (d) keep an incubator warm
20. 20.Which job needs a motion sensor? (a) start a fan when hot (b) open blinds at sunrise (c) close a window in rain (d) spot someone walking in
21. 21.⚙️ Which actuator would you use to move water to plants? (a) a motor (b) a pump (c) a buzzer (d) a display
22. 22.Which job needs a servo motor? (a) show a status light (b) turn to an exact angle (c) show the temperature (d) spin a robot’s wheels
23. 23.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an input (d) an output
24. 24.True or false: to keep an incubator warm, use a temperature sensor. (a) False (b) True
25. 25.True or false: to close a window in rain, use a gas sensor. (a) False (b) True
26. 26.🔍 Which sensor would you use to measure classroom noise? (a) a sound sensor (b) a light sensor (c) a gas sensor (d) a distance sensor
27. 27.🔍 Which sensor would you use to stop a robot near walls? (a) a soil moisture sensor (b) a motion sensor (c) a distance sensor (d) a gas sensor
28. 28.🔍 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)?
29. 29.🔍 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)?
30. 30.🔍 Which sensor would you use to close a window in rain? (a) a soil moisture sensor (b) a rain sensor (c) a sound sensor (d) a motion sensor
31. 31.🔍 Which sensor would you use to open blinds at sunrise? (a) a soil moisture sensor (b) a distance sensor (c) a gas sensor (d) a light sensor
32. 32.🔍 Which sensor would you use to make a parking alarm? (a) a motion sensor (b) a distance sensor (c) a sound sensor (d) a light sensor
33. 33.🔍 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)?
34. 34.🔍 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)?
35. 35.🔍 An object is 221 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 start a fan when hot? (a) a soil moisture sensor (b) a sound sensor (c) a rain sensor (d) a temperature sensor
37. 37.🔍 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)?
38. 38.⚙️ Which actuator would you use to show a status light? (a) a pump (b) an LED (c) a display (d) a buzzer
39. 39.🔍 A distance sensor sends a sound pulse and hears the echo 12 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
40. 40.🔍 An object is 119 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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