Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 49 · 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.🔍 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)?
2. 2.Which job needs a display? (a) show the temperature (b) open a gate to 90° (c) move water to plants (d) show a status light
3. 3.⚙️ Which actuator would you use to move water to plants? (a) a display (b) a buzzer (c) a motor (d) a pump
4. 4.🔍 Which sensor would you use to measure classroom noise? (a) a sound sensor (b) a light sensor (c) a motion sensor (d) a distance sensor
5. 5.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a fuse (c) a power source (d) an input
6. 6.⚙️ Which actuator would you use to turn to an exact angle? (a) a buzzer (b) a display (c) a motor (d) a servo motor
7. 7.Which job needs a gas sensor? (a) spot someone walking in (b) make a parking alarm (c) start a fan when hot (d) warn of a gas leak
8. 8.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a pump (b) an LED (c) a buzzer (d) a motor
9. 9.Which job needs a servo motor? (a) show a status light (b) move water to plants (c) beep an alarm (d) open a gate to 90°
10. 10.🔍 Which sensor would you use to make a parking alarm? (a) a light sensor (b) a distance sensor (c) a temperature sensor (d) a gas sensor
11. 11.Which job needs a motion sensor? (a) open blinds at sunrise (b) switch on with a clap (c) start a fan when hot (d) spot someone walking in
12. 12.🔍 Which sensor would you use to open blinds at sunrise? (a) a motion sensor (b) a distance sensor (c) a soil moisture sensor (d) a light sensor
13. 13.Which job needs a temperature sensor? (a) switch on lamps at dusk (b) warn of a gas leak (c) make a parking alarm (d) start a fan when hot
14. 14.Which job needs a temperature sensor? (a) make a parking alarm (b) close a window in rain (c) measure classroom noise (d) keep an incubator warm
15. 15.⚙️ What is an actuator? (a) a program (b) a sensor (c) a battery (d) an output that acts
16. 16.True or false: to switch on with a clap, use a temperature sensor. (a) False (b) True
17. 17.🔍 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?
18. 18.⚙️ Which actuator would you use to open a gate to 90°? (a) a motor (b) a servo motor (c) a buzzer (d) a pump
19. 19.True or false: to measure classroom noise, use a sound sensor. (a) False (b) True
20. 20.True or false: to warn of a gas leak, use a light sensor. (a) True (b) False
21. 21.🔍 A distance sensor sends a sound pulse and hears the echo 7 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
22. 22.True or false: to switch on with a clap, use a sound sensor. (a) False (b) True
23. 23.True or false: to start a fan when hot, use a motion sensor. (a) True (b) False
24. 24.Which job needs a pump? (a) move water to plants (b) beep an alarm (c) spin a robot’s wheels (d) show a status light
25. 25.Which job needs a motor? (a) beep an alarm (b) spin a robot’s wheels (c) open a gate to 90° (d) turn to an exact angle
26. 26.True or false: to switch on lamps at dusk, use a motion sensor. (a) False (b) True
27. 27.🔍 Which sensor would you use to warn of a gas leak? (a) a temperature sensor (b) a gas sensor (c) a sound sensor (d) a light sensor
28. 28.Which job needs an LED? (a) move water to plants (b) show a status light (c) turn to an exact angle (d) spin a robot’s wheels
29. 29.🔍 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?
30. 30.Which job needs a rain sensor? (a) keep an incubator warm (b) close a window in rain (c) water a dry plant (d) switch on lamps at dusk
31. 31.🔍 Which sensor would you use to switch on with a clap? (a) a gas sensor (b) a light sensor (c) a motion sensor (d) a sound sensor
32. 32.True or false: to switch on with a clap, use a gas sensor. (a) True (b) False
33. 33.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
34. 34.True or false: to close a window in rain, use a temperature sensor. (a) False (b) True
35. 35.🔍 Which sensor would you use to water a dry plant? (a) a distance sensor (b) a temperature sensor (c) a motion sensor (d) a soil moisture sensor
36. 36.True or false: to measure classroom noise, use a soil moisture sensor. (a) False (b) True
37. 37.Which job needs a distance sensor? (a) make a parking alarm (b) start a fan when hot (c) close a window in rain (d) switch on with a clap
38. 38.True or false: to spot someone walking in, use a soil moisture sensor. (a) True (b) False
39. 39.True or false: to spot someone walking in, use a motion sensor. (a) True (b) False
40. 40.🔍 Which sensor would you use to switch on lamps at dusk? (a) a sound sensor (b) a rain sensor (c) a light sensor (d) a motion sensor

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