Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 240 · 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 warn of a gas leak? (a) a gas sensor (b) a motion sensor (c) a temperature sensor (d) a rain sensor
2. 2.⚙️ Which actuator would you use to open a gate to 90°? (a) a display (b) a pump (c) an LED (d) a servo motor
3. 3.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a rain sensor (c) a soil moisture sensor (d) a motion sensor
4. 4.True or false: to switch on with a clap, use a temperature sensor. (a) True (b) False
5. 5.🔍 A distance sensor sends a sound pulse and hears the echo 3 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
6. 6.Which job needs a rain sensor? (a) close a window in rain (b) open blinds at sunrise (c) spot someone walking in (d) start a fan when hot
7. 7.🔍 An object is 153 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 motion sensor? (a) switch on lamps at dusk (b) close a window in rain (c) switch on with a clap (d) spot someone walking in
9. 9.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an input (c) an output (d) a fuse
10. 10.🔍 Which sensor would you use to make a parking alarm? (a) a distance sensor (b) a gas sensor (c) a temperature sensor (d) a soil moisture sensor
11. 11.⚙️ What is an actuator? (a) a battery (b) a sensor (c) a program (d) an output that acts
12. 12.Which job needs a display? (a) show the temperature (b) open a gate to 90° (c) show a status light (d) spin a robot’s wheels
13. 13.⚙️ Which actuator would you use to beep an alarm? (a) a motor (b) a display (c) a servo motor (d) a buzzer
14. 14.🔍 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?
15. 15.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
16. 16.⚙️ Which actuator would you use to turn to an exact angle? (a) a pump (b) a motor (c) a servo motor (d) a buzzer
17. 17.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
18. 18.True or false: to close a window in rain, use a distance sensor. (a) False (b) True
19. 19.True or false: to water a dry plant, use a rain sensor. (a) True (b) False
20. 20.Which job needs a servo motor? (a) beep an alarm (b) show a status light (c) spin a robot’s wheels (d) turn to an exact angle
21. 21.Which job needs a sound sensor? (a) open blinds at sunrise (b) stop a robot near walls (c) start a fan when hot (d) measure classroom noise
22. 22.Which job needs a soil moisture sensor? (a) keep an incubator warm (b) spot someone walking in (c) water a dry plant (d) switch on with a clap
23. 23.Which job needs a light sensor? (a) measure classroom noise (b) open blinds at sunrise (c) keep an incubator warm (d) stop a robot near walls
24. 24.Which job needs a light sensor? (a) keep an incubator warm (b) switch on lamps at dusk (c) make a parking alarm (d) water a dry plant
25. 25.True or false: to keep an incubator warm, use a temperature sensor. (a) False (b) True
26. 26.🔍 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?
27. 27.Which job needs a gas sensor? (a) open blinds at sunrise (b) warn of a gas leak (c) keep an incubator warm (d) stop a robot near walls
28. 28.🔍 A distance sensor sends a sound pulse and hears the echo 10 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
29. 29.🔍 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)?
30. 30.🔍 An object is 51 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
31. 31.🔍 Which sensor would you use to keep an incubator warm? (a) a temperature sensor (b) a distance sensor (c) a sound sensor (d) a soil moisture sensor
32. 32.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
33. 33.Which job needs a motor? (a) open a gate to 90° (b) spin a robot’s wheels (c) beep an alarm (d) show a status light
34. 34.🔍 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?
35. 35.🔍 Which sensor would you use to switch on lamps at dusk? (a) a light sensor (b) a distance sensor (c) a soil moisture sensor (d) a motion sensor
36. 36.🔍 Which sensor would you use to spot someone walking in? (a) a light sensor (b) a rain sensor (c) a soil moisture sensor (d) a motion sensor
37. 37.Which job needs a temperature sensor? (a) keep an incubator warm (b) open blinds at sunrise (c) stop a robot near walls (d) close a window in rain
38. 38.True or false: to make a parking alarm, use a motion sensor. (a) False (b) True
39. 39.True or false: to stop a robot near walls, use a motion sensor. (a) False (b) True
40. 40.🔍 A distance sensor sends a sound pulse and hears the echo 8 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?

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