Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 208 · 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 sensor would you use to close a window in rain? (a) a temperature sensor (b) a rain sensor (c) a motion sensor (d) a sound sensor
2. 2.🔍 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)?
3. 3.Which job needs a temperature sensor? (a) open blinds at sunrise (b) stop a robot near walls (c) start a fan when hot (d) measure classroom noise
4. 4.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a temperature sensor (c) a rain sensor (d) a motion sensor
5. 5.Which job needs a gas sensor? (a) switch on lamps at dusk (b) stop a robot near walls (c) measure classroom noise (d) warn of a gas leak
6. 6.⚙️ What is an actuator? (a) a battery (b) an output that acts (c) a program (d) a sensor
7. 7.🔍 A distance sensor sends a sound pulse and hears the echo 17 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
8. 8.Which job needs a light sensor? (a) switch on with a clap (b) keep an incubator warm (c) switch on lamps at dusk (d) spot someone walking in
9. 9.Which job needs a pump? (a) open a gate to 90° (b) move water to plants (c) spin a robot’s wheels (d) beep an alarm
10. 10.Which job needs a sound sensor? (a) start a fan when hot (b) measure classroom noise (c) make a parking alarm (d) water a dry plant
11. 11.🔍 Which sensor would you use to warn of a gas leak? (a) a motion sensor (b) a light sensor (c) a gas sensor (d) a distance sensor
12. 12.Which job needs a soil moisture sensor? (a) make a parking alarm (b) stop a robot near walls (c) start a fan when hot (d) water a dry plant
13. 13.🔍 Which sensor would you use to make a parking alarm? (a) a motion sensor (b) a light sensor (c) a distance sensor (d) a sound sensor
14. 14.🔍 Which sensor would you use to open blinds at sunrise? (a) a soil moisture sensor (b) a rain sensor (c) a temperature sensor (d) a light sensor
15. 15.🔍 An object is 238 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
16. 16.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an input (c) a fuse (d) an output
17. 17.🔍 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)?
18. 18.🔍 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?
19. 19.⚙️ Which actuator would you use to show a status light? (a) a pump (b) a buzzer (c) an LED (d) a servo motor
20. 20.True or false: to open blinds at sunrise, use a motion sensor. (a) False (b) True
21. 21.True or false: to measure classroom noise, use a sound sensor. (a) True (b) False
22. 22.🔍 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)?
23. 23.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
24. 24.🔍 Which sensor would you use to measure classroom noise? (a) a rain sensor (b) a gas sensor (c) a sound sensor (d) a soil moisture sensor
25. 25.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) a motor (c) an LED (d) a servo motor
26. 26.Which job needs a motor? (a) turn to an exact angle (b) beep an alarm (c) spin a robot’s wheels (d) show the temperature
27. 27.True or false: to stop a robot near walls, use a motion sensor. (a) False (b) True
28. 28.True or false: to switch on with a clap, use a temperature sensor. (a) True (b) False
29. 29.🔍 Which sensor would you use to keep an incubator warm? (a) a sound sensor (b) a soil moisture sensor (c) a motion sensor (d) a temperature sensor
30. 30.🔍 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?
31. 31.🔍 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)?
32. 32.🔍 A distance sensor sends a sound pulse and hears the echo 13 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
33. 33.⚙️ Which actuator would you use to open a gate to 90°? (a) a motor (b) a display (c) a buzzer (d) a servo motor
34. 34.🔍 A distance sensor sends a sound pulse and hears the echo 9 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 2 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
36. 36.⚙️ Which actuator would you use to show the temperature? (a) a buzzer (b) a display (c) a motor (d) an LED
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.True or false: to open blinds at sunrise, use a light sensor. (a) True (b) False
39. 39.Which job needs a sound sensor? (a) switch on lamps at dusk (b) keep an incubator warm (c) open blinds at sunrise (d) switch on with a clap
40. 40.🔍 Which sensor would you use to water a dry plant? (a) a soil moisture sensor (b) a motion sensor (c) a temperature sensor (d) a distance sensor

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