Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 163 · 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 job needs a temperature sensor? (a) open blinds at sunrise (b) switch on with a clap (c) water a dry plant (d) keep an incubator warm
2. 2.Which job needs a soil moisture sensor? (a) keep an incubator warm (b) close a window in rain (c) water a dry plant (d) start a fan when hot
3. 3.🔍 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?
4. 4.Which job needs a light sensor? (a) spot someone walking in (b) keep an incubator warm (c) stop a robot near walls (d) open blinds at sunrise
5. 5.Which job needs a motor? (a) show a status light (b) turn to an exact angle (c) beep an alarm (d) spin a robot’s wheels
6. 6.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an output (c) an input (d) a fuse
7. 7.⚙️ What is an actuator? (a) a program (b) a sensor (c) a battery (d) an output that acts
8. 8.⚙️ Which actuator would you use to show a status light? (a) a buzzer (b) a pump (c) a motor (d) an LED
9. 9.Which job needs a distance sensor? (a) stop a robot near walls (b) open blinds at sunrise (c) water a dry plant (d) start a fan when hot
10. 10.🔍 Which sensor would you use to spot someone walking in? (a) a motion sensor (b) a light sensor (c) a soil moisture sensor (d) a distance sensor
11. 11.Which job needs a gas sensor? (a) open blinds at sunrise (b) keep an incubator warm (c) make a parking alarm (d) warn of a gas leak
12. 12.🔍 Which sensor would you use to switch on lamps at dusk? (a) a soil moisture sensor (b) a gas sensor (c) a sound sensor (d) a light sensor
13. 13.🔍 Which sensor would you use to stop a robot near walls? (a) a temperature sensor (b) a sound sensor (c) a motion sensor (d) a distance sensor
14. 14.🔍 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?
15. 15.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
16. 16.🔍 Which sensor would you use to water a dry plant? (a) a rain sensor (b) a motion sensor (c) a soil moisture sensor (d) a gas sensor
17. 17.🔍 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)?
18. 18.🔍 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?
19. 19.Which job needs a motion sensor? (a) keep an incubator warm (b) spot someone walking in (c) switch on lamps at dusk (d) open blinds at sunrise
20. 20.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
21. 21.🔍 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)?
22. 22.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
23. 23.True or false: to open blinds at sunrise, use a soil moisture sensor. (a) False (b) True
24. 24.🔍 Which sensor would you use to keep an incubator warm? (a) a motion sensor (b) a distance sensor (c) a temperature sensor (d) a soil moisture sensor
25. 25.True or false: to switch on with a clap, use a light sensor. (a) True (b) False
26. 26.Which job needs a buzzer? (a) turn to an exact angle (b) spin a robot’s wheels (c) beep an alarm (d) show a status light
27. 27.⚙️ Which actuator would you use to open a gate to 90°? (a) a motor (b) a buzzer (c) an LED (d) a servo motor
28. 28.Which job needs a rain sensor? (a) close a window in rain (b) switch on with a clap (c) stop a robot near walls (d) make a parking alarm
29. 29.🔍 Which sensor would you use to warn of a gas leak? (a) a light sensor (b) a motion sensor (c) a gas sensor (d) a distance sensor
30. 30.Which job needs a display? (a) show the temperature (b) open a gate to 90° (c) beep an alarm (d) spin a robot’s wheels
31. 31.🔍 Which sensor would you use to close a window in rain? (a) a motion sensor (b) a gas sensor (c) a distance sensor (d) a rain sensor
32. 32.🔍 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)?
33. 33.True or false: to switch on with a clap, use a sound sensor. (a) False (b) True
34. 34.⚙️ Which actuator would you use to turn to an exact angle? (a) an LED (b) a buzzer (c) a pump (d) a servo motor
35. 35.Which job needs an LED? (a) move water to plants (b) open a gate to 90° (c) show the temperature (d) show a status light
36. 36.🔍 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?
37. 37.🔍 Which sensor would you use to switch on with a clap? (a) a light sensor (b) a sound sensor (c) a temperature sensor (d) a motion sensor
38. 38.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) an LED (c) a servo motor (d) a motor
39. 39.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
40. 40.Which job needs a servo motor? (a) open a gate to 90° (b) beep an alarm (c) spin a robot’s wheels (d) move water to plants

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