Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 99 · 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 close a window in rain, use a rain sensor. (a) True (b) False
2. 2.Which job needs a pump? (a) show the temperature (b) spin a robot’s wheels (c) show a status light (d) move water to plants
3. 3.Which job needs a light sensor? (a) water a dry plant (b) close a window in rain (c) switch on lamps at dusk (d) stop a robot near walls
4. 4.🔍 Which sensor would you use to start a fan when hot? (a) a soil moisture sensor (b) a rain sensor (c) a sound sensor (d) a temperature sensor
5. 5.Which job needs a display? (a) open a gate to 90° (b) show a status light (c) spin a robot’s wheels (d) show the temperature
6. 6.Which job needs a distance sensor? (a) switch on with a clap (b) water a dry plant (c) make a parking alarm (d) open blinds at sunrise
7. 7.⚙️ What is an actuator? (a) a sensor (b) a battery (c) a program (d) an output that acts
8. 8.Which job needs an LED? (a) spin a robot’s wheels (b) show a status light (c) move water to plants (d) beep an alarm
9. 9.🔍 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?
10. 10.🔍 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 sound sensor
11. 11.Which job needs a gas sensor? (a) open blinds at sunrise (b) close a window in rain (c) switch on with a clap (d) warn of a gas leak
12. 12.Which job needs a servo motor? (a) move water to plants (b) open a gate to 90° (c) show a status light (d) show the temperature
13. 13.Which job needs a buzzer? (a) turn to an exact angle (b) open a gate to 90° (c) beep an alarm (d) show a status light
14. 14.True or false: to keep an incubator warm, use a light sensor. (a) True (b) False
15. 15.🔍 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?
16. 16.True or false: to warn of a gas leak, use a soil moisture sensor. (a) True (b) False
17. 17.True or false: to water a dry plant, use a soil moisture sensor. (a) False (b) True
18. 18.🔍 Which sensor would you use to spot someone walking in? (a) a temperature sensor (b) a motion sensor (c) a distance sensor (d) a rain sensor
19. 19.🔍 Which sensor would you use to switch on lamps at dusk? (a) a gas sensor (b) a motion sensor (c) a temperature sensor (d) a light sensor
20. 20.Which job needs a soil moisture sensor? (a) warn of a gas leak (b) make a parking alarm (c) water a dry plant (d) switch on with a clap
21. 21.🔍 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)?
22. 22.🔍 An object is 289 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
23. 23.Which job needs a temperature sensor? (a) switch on lamps at dusk (b) stop a robot near walls (c) switch on with a clap (d) start a fan when hot
24. 24.🔍 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)?
25. 25.⚙️ Which actuator would you use to move water to plants? (a) a pump (b) an LED (c) a servo motor (d) a motor
26. 26.Which job needs a servo motor? (a) spin a robot’s wheels (b) show a status light (c) move water to plants (d) turn to an exact angle
27. 27.Which job needs a sound sensor? (a) start a fan when hot (b) warn of a gas leak (c) switch on with a clap (d) open blinds at sunrise
28. 28.⚙️ Which actuator would you use to open a gate to 90°? (a) a servo motor (b) a display (c) a pump (d) an LED
29. 29.Which job needs a sound sensor? (a) make a parking alarm (b) water a dry plant (c) switch on lamps at dusk (d) measure classroom noise
30. 30.🔍 Which sensor would you use to close a window in rain? (a) a rain sensor (b) a temperature sensor (c) a soil moisture sensor (d) a light sensor
31. 31.⚙️ Which actuator would you use to show the temperature? (a) a servo motor (b) a buzzer (c) a motor (d) a display
32. 32.🔍 Which sensor would you use to measure classroom noise? (a) a temperature sensor (b) a light sensor (c) a sound sensor (d) a soil moisture sensor
33. 33.🔍 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?
34. 34.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a power source (c) a fuse (d) an input
35. 35.True or false: to keep an incubator warm, use a temperature sensor. (a) False (b) True
36. 36.🔍 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?
37. 37.Which job needs a motor? (a) beep an alarm (b) open a gate to 90° (c) turn to an exact angle (d) spin a robot’s wheels
38. 38.Which job needs a temperature sensor? (a) keep an incubator warm (b) close a window in rain (c) make a parking alarm (d) measure classroom noise
39. 39.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) an LED (c) a motor (d) a servo motor
40. 40.True or false: to switch on with a clap, use a temperature sensor. (a) True (b) False

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