Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 94 · 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 spot someone walking in, use a motion sensor. (a) False (b) True
2. 2.🔍 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)?
3. 3.Which job needs a buzzer? (a) show a status light (b) spin a robot’s wheels (c) beep an alarm (d) show the temperature
4. 4.True or false: to switch on lamps at dusk, use a soil moisture sensor. (a) True (b) False
5. 5.🔍 Which sensor would you use to measure classroom noise? (a) a temperature sensor (b) a sound sensor (c) a soil moisture sensor (d) a distance sensor
6. 6.🔍 Which sensor would you use to close a window in rain? (a) a rain sensor (b) a light sensor (c) a soil moisture sensor (d) a distance sensor
7. 7.True or false: to keep an incubator warm, use a temperature sensor. (a) True (b) False
8. 8.True or false: to make a parking alarm, use a light sensor. (a) False (b) True
9. 9.🔍 An object is 306 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
10. 10.True or false: to stop a robot near walls, use a distance sensor. (a) True (b) False
11. 11.Which job needs a servo motor? (a) move water to plants (b) show a status light (c) spin a robot’s wheels (d) open a gate to 90°
12. 12.Which job needs an LED? (a) open a gate to 90° (b) turn to an exact angle (c) spin a robot’s wheels (d) show a status light
13. 13.🔍 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?
14. 14.True or false: to start a fan when hot, use a gas sensor. (a) False (b) True
15. 15.🔍 Which sensor would you use to stop a robot near walls? (a) a light sensor (b) a sound sensor (c) a rain sensor (d) a distance sensor
16. 16.Which job needs a motor? (a) show a status light (b) show the temperature (c) beep an alarm (d) spin a robot’s wheels
17. 17.🔍 Which sensor would you use to switch on with a clap? (a) a light sensor (b) a soil moisture sensor (c) a sound sensor (d) a gas sensor
18. 18.🔍 Which sensor would you use to open blinds at sunrise? (a) a temperature sensor (b) a rain sensor (c) a sound sensor (d) a light sensor
19. 19.🔍 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?
20. 20.True or false: to stop a robot near walls, use a light sensor. (a) True (b) False
21. 21.⚙️ Which actuator would you use to move water to plants? (a) a servo motor (b) a pump (c) an LED (d) a display
22. 22.🔍 Which sensor would you use to warn of a gas leak? (a) a light sensor (b) a temperature sensor (c) a distance sensor (d) a gas sensor
23. 23.⚙️ Which actuator would you use to beep an alarm? (a) a display (b) a motor (c) a servo motor (d) a buzzer
24. 24.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
25. 25.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
26. 26.⚙️ Which actuator would you use to show a status light? (a) a servo motor (b) an LED (c) a display (d) a buzzer
27. 27.🔍 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)?
28. 28.Which job needs a soil moisture sensor? (a) water a dry plant (b) measure classroom noise (c) open blinds at sunrise (d) stop a robot near walls
29. 29.Which job needs a rain sensor? (a) warn of a gas leak (b) make a parking alarm (c) stop a robot near walls (d) close a window in rain
30. 30.🔍 For a microcontroller, is a sensor an input or an output? (a) an input (b) a power source (c) an output (d) a fuse
31. 31.🔍 Which sensor would you use to keep an incubator warm? (a) a temperature sensor (b) a soil moisture sensor (c) a gas sensor (d) a light sensor
32. 32.🔍 Which sensor would you use to start a fan when hot? (a) a distance sensor (b) a gas sensor (c) a temperature sensor (d) a sound sensor
33. 33.Which job needs a gas sensor? (a) measure classroom noise (b) make a parking alarm (c) stop a robot near walls (d) warn of a gas leak
34. 34.True or false: to measure classroom noise, use a rain sensor. (a) False (b) True
35. 35.⚙️ Which actuator would you use to turn to an exact angle? (a) a display (b) a pump (c) a motor (d) a servo motor
36. 36.⚙️ What is an actuator? (a) a sensor (b) a battery (c) an output that acts (d) a program
37. 37.Which job needs a pump? (a) beep an alarm (b) move water to plants (c) show the temperature (d) open a gate to 90°
38. 38.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a servo motor (c) a buzzer (d) a motor
39. 39.True or false: to switch on lamps at dusk, use a light sensor. (a) True (b) False
40. 40.🔍 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?

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