Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 12 · 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.True or false: to switch on lamps at dusk, use a gas sensor. (a) False (b) True
2. 2.Which job needs an LED? (a) show a status light (b) show the temperature (c) beep an alarm (d) move water to plants
3. 3.Which job needs a soil moisture sensor? (a) start a fan when hot (b) stop a robot near walls (c) water a dry plant (d) measure classroom noise
4. 4.⚙️ Which actuator would you use to show a status light? (a) an LED (b) a pump (c) a display (d) a servo motor
5. 5.🔍 Which sensor would you use to warn of a gas leak? (a) a rain sensor (b) a gas sensor (c) a light sensor (d) a soil moisture sensor
6. 6.🔍 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)?
7. 7.Which job needs a buzzer? (a) spin a robot’s wheels (b) beep an alarm (c) open a gate to 90° (d) turn to an exact angle
8. 8.🔍 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)?
9. 9.Which job needs a motor? (a) beep an alarm (b) spin a robot’s wheels (c) turn to an exact angle (d) show a status light
10. 10.Which job needs a temperature sensor? (a) warn of a gas leak (b) spot someone walking in (c) measure classroom noise (d) keep an incubator warm
11. 11.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
12. 12.True or false: to measure classroom noise, use a light sensor. (a) True (b) False
13. 13.⚙️ Which actuator would you use to show the temperature? (a) a motor (b) a display (c) an LED (d) a servo motor
14. 14.Which job needs a servo motor? (a) move water to plants (b) turn to an exact angle (c) show the temperature (d) show a status light
15. 15.🔍 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)?
16. 16.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an input (d) an output
17. 17.🔍 An object is 255 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 13 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
19. 19.🔍 Which sensor would you use to switch on lamps at dusk? (a) a temperature sensor (b) a soil moisture sensor (c) a motion sensor (d) a light sensor
20. 20.Which job needs a distance sensor? (a) keep an incubator warm (b) make a parking alarm (c) open blinds at sunrise (d) warn of a gas leak
21. 21.🔍 A distance sensor sends a sound pulse and hears the echo 16 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
22. 22.🔍 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?
23. 23.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a pump (c) a servo motor (d) an LED
24. 24.⚙️ What is an actuator? (a) an output that acts (b) a battery (c) a program (d) a sensor
25. 25.True or false: to warn of a gas leak, use a temperature sensor. (a) True (b) False
26. 26.Which job needs a pump? (a) move water to plants (b) open a gate to 90° (c) show a status light (d) beep an alarm
27. 27.Which job needs a servo motor? (a) open a gate to 90° (b) show a status light (c) spin a robot’s wheels (d) beep an alarm
28. 28.🔍 Which sensor would you use to switch on with a clap? (a) a sound sensor (b) a light sensor (c) a gas sensor (d) a motion sensor
29. 29.True or false: to open blinds at sunrise, use a light sensor. (a) True (b) False
30. 30.Which job needs a rain sensor? (a) close a window in rain (b) warn of a gas leak (c) stop a robot near walls (d) switch on with a clap
31. 31.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
32. 32.⚙️ Which actuator would you use to open a gate to 90°? (a) a pump (b) an LED (c) a servo motor (d) a motor
33. 33.⚙️ Which actuator would you use to beep an alarm? (a) a display (b) a buzzer (c) a motor (d) a pump
34. 34.True or false: to water a dry plant, use a distance sensor. (a) True (b) False
35. 35.True or false: to stop a robot near walls, use a gas sensor. (a) False (b) True
36. 36.⚙️ Which actuator would you use to spin a robot’s wheels? (a) an LED (b) a pump (c) a servo motor (d) a motor
37. 37.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
38. 38.🔍 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?
39. 39.🔍 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)?
40. 40.Which job needs a distance sensor? (a) stop a robot near walls (b) open blinds at sunrise (c) water a dry plant (d) warn of a gas leak

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