Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 333 · 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 11 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
2. 2.True or false: to keep an incubator warm, use a rain sensor. (a) True (b) False
3. 3.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
4. 4.🔍 An object is 289 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
5. 5.🔍 Which sensor would you use to start a fan when hot? (a) a temperature sensor (b) a motion sensor (c) a rain sensor (d) a sound sensor
6. 6.Which job needs an LED? (a) beep an alarm (b) show a status light (c) turn to an exact angle (d) spin a robot’s wheels
7. 7.🔍 Which sensor would you use to close a window in rain? (a) a gas sensor (b) a rain sensor (c) a light sensor (d) a motion sensor
8. 8.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
9. 9.Which job needs a motion sensor? (a) spot someone walking in (b) measure classroom noise (c) keep an incubator warm (d) stop a robot near walls
10. 10.🔍 Which sensor would you use to open blinds at sunrise? (a) a distance sensor (b) a sound sensor (c) a light sensor (d) a rain sensor
11. 11.Which job needs a pump? (a) move water to plants (b) turn to an exact angle (c) beep an alarm (d) show the temperature
12. 12.⚙️ Which actuator would you use to spin a robot’s wheels? (a) an LED (b) a buzzer (c) a motor (d) a display
13. 13.True or false: to start a fan when hot, use a soil moisture sensor. (a) True (b) False
14. 14.⚙️ Which actuator would you use to turn to an exact angle? (a) an LED (b) a motor (c) a buzzer (d) a servo motor
15. 15.Which job needs a light sensor? (a) keep an incubator warm (b) switch on lamps at dusk (c) switch on with a clap (d) close a window in rain
16. 16.True or false: to warn of a gas leak, use a motion sensor. (a) True (b) False
17. 17.🔍 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?
18. 18.🔍 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)?
19. 19.Which job needs a gas sensor? (a) warn of a gas leak (b) measure classroom noise (c) make a parking alarm (d) spot someone walking in
20. 20.⚙️ Which actuator would you use to show the temperature? (a) a pump (b) a buzzer (c) a display (d) a servo motor
21. 21.🔍 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?
22. 22.🔍 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?
23. 23.Which job needs a soil moisture sensor? (a) warn of a gas leak (b) close a window in rain (c) water a dry plant (d) make a parking alarm
24. 24.Which job needs a servo motor? (a) move water to plants (b) spin a robot’s wheels (c) show a status light (d) open a gate to 90°
25. 25.True or false: to open blinds at sunrise, use a motion sensor. (a) False (b) True
26. 26.🔍 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?
27. 27.🔍 An object is 51 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
28. 28.True or false: to spot someone walking in, use a motion sensor. (a) True (b) False
29. 29.⚙️ Which actuator would you use to move water to plants? (a) a motor (b) a buzzer (c) a pump (d) an LED
30. 30.Which job needs a motor? (a) open a gate to 90° (b) turn to an exact angle (c) spin a robot’s wheels (d) show a status light
31. 31.⚙️ What is an actuator? (a) a sensor (b) a program (c) an output that acts (d) a battery
32. 32.🔍 Which sensor would you use to warn of a gas leak? (a) a distance sensor (b) a gas sensor (c) a sound sensor (d) a soil moisture sensor
33. 33.Which job needs a rain sensor? (a) open blinds at sunrise (b) switch on lamps at dusk (c) start a fan when hot (d) close a window in rain
34. 34.🔍 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)?
35. 35.🔍 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)?
36. 36.🔍 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?
37. 37.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a gas sensor (c) a sound sensor (d) a rain sensor
38. 38.Which job needs a display? (a) open a gate to 90° (b) beep an alarm (c) show the temperature (d) spin a robot’s wheels
39. 39.Which job needs a temperature sensor? (a) stop a robot near walls (b) start a fan when hot (c) open blinds at sunrise (d) make a parking alarm
40. 40.⚙️ Which actuator would you use to beep an alarm? (a) a servo motor (b) a motor (c) a buzzer (d) a display

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