Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 50 · 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 switch on lamps at dusk? (a) a sound sensor (b) a light sensor (c) a rain sensor (d) a soil moisture sensor
2. 2.🔍 Which sensor would you use to keep an incubator warm? (a) a soil moisture sensor (b) a gas sensor (c) a temperature sensor (d) a sound sensor
3. 3.⚙️ Which actuator would you use to show a status light? (a) a pump (b) an LED (c) a motor (d) a buzzer
4. 4.Which job needs a display? (a) turn to an exact angle (b) spin a robot’s wheels (c) show a status light (d) show the temperature
5. 5.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
6. 6.🔍 Which sensor would you use to start a fan when hot? (a) a motion sensor (b) a temperature sensor (c) a gas sensor (d) a soil moisture sensor
7. 7.Which job needs a pump? (a) show the temperature (b) spin a robot’s wheels (c) turn to an exact angle (d) move water to plants
8. 8.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) an output (c) a power source (d) a fuse
9. 9.True or false: to start a fan when hot, use a soil moisture sensor. (a) True (b) False
10. 10.🔍 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)?
11. 11.🔍 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?
12. 12.🔍 Which sensor would you use to make a parking alarm? (a) a light sensor (b) a soil moisture sensor (c) a distance sensor (d) a temperature sensor
13. 13.⚙️ Which actuator would you use to turn to an exact angle? (a) a display (b) a motor (c) a servo motor (d) a buzzer
14. 14.Which job needs a sound sensor? (a) start a fan when hot (b) warn of a gas leak (c) keep an incubator warm (d) switch on with a clap
15. 15.⚙️ Which actuator would you use to open a gate to 90°? (a) a buzzer (b) a display (c) a servo motor (d) a pump
16. 16.Which job needs a servo motor? (a) spin a robot’s wheels (b) move water to plants (c) show the temperature (d) open a gate to 90°
17. 17.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
18. 18.🔍 Which sensor would you use to warn of a gas leak? (a) a sound sensor (b) a temperature sensor (c) a distance sensor (d) a gas sensor
19. 19.🔍 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?
20. 20.⚙️ Which actuator would you use to show the temperature? (a) a pump (b) a display (c) an LED (d) a motor
21. 21.🔍 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)?
22. 22.True or false: to warn of a gas leak, use a temperature sensor. (a) False (b) True
23. 23.🔍 Which sensor would you use to water a dry plant? (a) a light sensor (b) a gas sensor (c) a sound sensor (d) a soil moisture sensor
24. 24.Which job needs a motion sensor? (a) keep an incubator warm (b) open blinds at sunrise (c) spot someone walking in (d) make a parking alarm
25. 25.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
26. 26.Which job needs a light sensor? (a) close a window in rain (b) water a dry plant (c) keep an incubator warm (d) switch on lamps at dusk
27. 27.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
28. 28.Which job needs a soil moisture sensor? (a) start a fan when hot (b) water a dry plant (c) switch on lamps at dusk (d) close a window in rain
29. 29.🔍 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)?
30. 30.True or false: to warn of a gas leak, use a light sensor. (a) False (b) True
31. 31.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
32. 32.Which job needs a servo motor? (a) turn to an exact angle (b) move water to plants (c) beep an alarm (d) spin a robot’s wheels
33. 33.🔍 An object is 34 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
34. 34.True or false: to keep an incubator warm, use a temperature sensor. (a) False (b) True
35. 35.⚙️ Which actuator would you use to spin a robot’s wheels? (a) an LED (b) a motor (c) a servo motor (d) a pump
36. 36.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
37. 37.True or false: to open blinds at sunrise, use a temperature sensor. (a) True (b) False
38. 38.⚙️ What is an actuator? (a) a program (b) an output that acts (c) a battery (d) a sensor
39. 39.🔍 Which sensor would you use to switch on with a clap? (a) a motion sensor (b) a temperature sensor (c) a sound sensor (d) a soil moisture sensor
40. 40.True or false: to close a window in rain, use a sound sensor. (a) False (b) True

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids