Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 331 · 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 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
2. 2.Which job needs a sound sensor? (a) warn of a gas leak (b) water a dry plant (c) make a parking alarm (d) measure classroom noise
3. 3.Which job needs a pump? (a) spin a robot’s wheels (b) move water to plants (c) turn to an exact angle (d) open a gate to 90°
4. 4.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
5. 5.⚙️ What is an actuator? (a) a battery (b) a program (c) an output that acts (d) a sensor
6. 6.🔍 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?
7. 7.🔍 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?
8. 8.Which job needs a motor? (a) spin a robot’s wheels (b) show a status light (c) show the temperature (d) beep an alarm
9. 9.True or false: to measure classroom noise, use a soil moisture sensor. (a) False (b) True
10. 10.🔍 Which sensor would you use to switch on with a clap? (a) a sound sensor (b) a rain sensor (c) a soil moisture sensor (d) a temperature sensor
11. 11.🔍 An object is 85 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
12. 12.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a display (b) a motor (c) an LED (d) a servo motor
13. 13.⚙️ Which actuator would you use to show a status light? (a) a servo motor (b) a buzzer (c) a motor (d) an LED
14. 14.True or false: to warn of a gas leak, use a gas sensor. (a) True (b) False
15. 15.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) an input (c) a power source (d) a fuse
16. 16.True or false: to close a window in rain, use a rain sensor. (a) True (b) False
17. 17.🔍 Which sensor would you use to start a fan when hot? (a) a soil moisture sensor (b) a temperature sensor (c) a sound sensor (d) a light sensor
18. 18.🔍 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)?
19. 19.Which job needs a gas sensor? (a) switch on lamps at dusk (b) stop a robot near walls (c) warn of a gas leak (d) switch on with a clap
20. 20.⚙️ Which actuator would you use to move water to plants? (a) a display (b) a pump (c) a servo motor (d) a motor
21. 21.Which job needs an LED? (a) turn to an exact angle (b) show a status light (c) spin a robot’s wheels (d) open a gate to 90°
22. 22.🔍 Which sensor would you use to stop a robot near walls? (a) a temperature sensor (b) a distance sensor (c) a rain sensor (d) a motion sensor
23. 23.🔍 Which sensor would you use to open blinds at sunrise? (a) a distance sensor (b) a light sensor (c) a sound sensor (d) a motion sensor
24. 24.⚙️ Which actuator would you use to beep an alarm? (a) an LED (b) a pump (c) a motor (d) a buzzer
25. 25.True or false: to open blinds at sunrise, use a soil moisture sensor. (a) True (b) False
26. 26.Which job needs a soil moisture sensor? (a) water a dry plant (b) switch on with a clap (c) open blinds at sunrise (d) switch on lamps at dusk
27. 27.Which job needs a buzzer? (a) open a gate to 90° (b) move water to plants (c) beep an alarm (d) show a status light
28. 28.Which job needs a temperature sensor? (a) close a window in rain (b) start a fan when hot (c) open blinds at sunrise (d) water a dry plant
29. 29.🔍 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)?
30. 30.🔍 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)?
31. 31.🔍 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)?
32. 32.Which job needs a sound sensor? (a) close a window in rain (b) open blinds at sunrise (c) warn of a gas leak (d) switch on with a clap
33. 33.Which job needs a motion sensor? (a) water a dry plant (b) open blinds at sunrise (c) make a parking alarm (d) spot someone walking in
34. 34.⚙️ Which actuator would you use to show the temperature? (a) a pump (b) an LED (c) a motor (d) a display
35. 35.🔍 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?
36. 36.🔍 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?
37. 37.True or false: to switch on with a clap, use a rain sensor. (a) False (b) True
38. 38.True or false: to spot someone walking in, use a gas sensor. (a) False (b) True
39. 39.Which job needs a display? (a) beep an alarm (b) show a status light (c) show the temperature (d) move water to plants
40. 40.Which job needs a servo motor? (a) spin a robot’s wheels (b) beep an alarm (c) show a status light (d) open a gate to 90°

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