Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 330 · 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 switch on lamps at dusk, use a rain sensor. (a) True (b) False
2. 2.🔍 A distance sensor sends a sound pulse and hears the echo 1 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
3. 3.🔍 Which sensor would you use to make a parking alarm? (a) a sound sensor (b) a light sensor (c) a distance sensor (d) a motion sensor
4. 4.🔍 Which sensor would you use to spot someone walking in? (a) a motion sensor (b) a temperature sensor (c) a sound sensor (d) a rain sensor
5. 5.🔍 A distance sensor sends a sound pulse and hears the echo 16 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
6. 6.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) a fuse (c) an output (d) an input
7. 7.Which job needs a gas sensor? (a) switch on lamps at dusk (b) open blinds at sunrise (c) warn of a gas leak (d) switch on with a clap
8. 8.Which job needs a pump? (a) turn to an exact angle (b) move water to plants (c) show the temperature (d) spin a robot’s wheels
9. 9.Which job needs a motion sensor? (a) close a window in rain (b) spot someone walking in (c) switch on lamps at dusk (d) water a dry plant
10. 10.🔍 A distance sensor sends a sound pulse and hears the echo 17 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
11. 11.Which job needs a rain sensor? (a) switch on lamps at dusk (b) start a fan when hot (c) close a window in rain (d) measure classroom noise
12. 12.🔍 A distance sensor sends a sound pulse and hears the echo 12 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
13. 13.True or false: to keep an incubator warm, use a temperature sensor. (a) True (b) False
14. 14.True or false: to keep an incubator warm, use a gas sensor. (a) True (b) False
15. 15.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a servo motor (c) an LED (d) a motor
16. 16.Which job needs a temperature sensor? (a) start a fan when hot (b) switch on lamps at dusk (c) make a parking alarm (d) switch on with a clap
17. 17.🔍 Which sensor would you use to switch on with a clap? (a) a motion sensor (b) a distance sensor (c) a sound sensor (d) a light sensor
18. 18.🔍 Which sensor would you use to measure classroom noise? (a) a temperature sensor (b) a sound sensor (c) a motion sensor (d) a light sensor
19. 19.🔍 Which sensor would you use to warn of a gas leak? (a) a sound sensor (b) a light sensor (c) a gas sensor (d) a rain sensor
20. 20.True or false: to stop a robot near walls, use a temperature sensor. (a) True (b) False
21. 21.True or false: to switch on with a clap, use a temperature sensor. (a) True (b) False
22. 22.Which job needs a soil moisture sensor? (a) open blinds at sunrise (b) switch on lamps at dusk (c) start a fan when hot (d) water a dry plant
23. 23.⚙️ What is an actuator? (a) a sensor (b) an output that acts (c) a battery (d) a program
24. 24.Which job needs a light sensor? (a) water a dry plant (b) spot someone walking in (c) make a parking alarm (d) open blinds at sunrise
25. 25.True or false: to warn of a gas leak, use a gas sensor. (a) True (b) False
26. 26.Which job needs a motor? (a) show a status light (b) open a gate to 90° (c) show the temperature (d) spin a robot’s wheels
27. 27.🔍 Which sensor would you use to open blinds at sunrise? (a) a soil moisture sensor (b) a distance sensor (c) a sound sensor (d) a light sensor
28. 28.🔍 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)?
29. 29.🔍 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?
30. 30.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) a motor (c) a servo motor (d) a pump
31. 31.Which job needs a display? (a) show the temperature (b) show a status light (c) move water to plants (d) spin a robot’s wheels
32. 32.⚙️ Which actuator would you use to open a gate to 90°? (a) an LED (b) a pump (c) a servo motor (d) a display
33. 33.True or false: to close a window in rain, use a rain sensor. (a) True (b) False
34. 34.True or false: to start a fan when hot, use a light sensor. (a) True (b) False
35. 35.⚙️ Which actuator would you use to show a status light? (a) a buzzer (b) a motor (c) a servo motor (d) an LED
36. 36.True or false: to spot someone walking in, use a motion sensor. (a) True (b) False
37. 37.🔍 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?
38. 38.True or false: to warn of a gas leak, use a distance sensor. (a) True (b) False
39. 39.True or false: to switch on lamps at dusk, use a gas sensor. (a) False (b) True
40. 40.True or false: to make a parking alarm, use a motion sensor. (a) False (b) True

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