Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 324 · 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 switch on with a clap? (a) a distance sensor (b) a sound sensor (c) a temperature sensor (d) a gas sensor
2. 2.True or false: to spot someone walking in, use a temperature sensor. (a) True (b) False
3. 3.Which job needs a motion sensor? (a) stop a robot near walls (b) water a dry plant (c) measure classroom noise (d) spot someone walking in
4. 4.Which job needs a motor? (a) beep an alarm (b) show the temperature (c) open a gate to 90° (d) spin a robot’s wheels
5. 5.🔍 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)?
6. 6.True or false: to switch on with a clap, use a sound sensor. (a) False (b) True
7. 7.True or false: to keep an incubator warm, use a rain sensor. (a) True (b) False
8. 8.🔍 Which sensor would you use to spot someone walking in? (a) a motion sensor (b) a rain sensor (c) a temperature sensor (d) a soil moisture sensor
9. 9.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) an output (c) an input (d) a fuse
10. 10.🔍 A distance sensor sends a sound pulse and hears the echo 6 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
11. 11.Which job needs a buzzer? (a) spin a robot’s wheels (b) turn to an exact angle (c) show the temperature (d) beep an alarm
12. 12.🔍 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)?
13. 13.🔍 Which sensor would you use to water a dry plant? (a) a rain sensor (b) a soil moisture sensor (c) a temperature sensor (d) a distance sensor
14. 14.Which job needs a soil moisture sensor? (a) stop a robot near walls (b) make a parking alarm (c) warn of a gas leak (d) water a dry plant
15. 15.True or false: to open blinds at sunrise, use a light sensor. (a) True (b) False
16. 16.⚙️ What is an actuator? (a) a sensor (b) a battery (c) a program (d) an output that acts
17. 17.True or false: to keep an incubator warm, use a soil moisture sensor. (a) False (b) True
18. 18.⚙️ Which actuator would you use to open a gate to 90°? (a) a pump (b) a display (c) an LED (d) a servo motor
19. 19.Which job needs a temperature sensor? (a) measure classroom noise (b) start a fan when hot (c) switch on lamps at dusk (d) water a dry plant
20. 20.🔍 Which sensor would you use to start a fan when hot? (a) a rain sensor (b) a temperature sensor (c) a sound sensor (d) a motion sensor
21. 21.🔍 A distance sensor sends a sound pulse and hears the echo 14 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
22. 22.Which job needs a distance sensor? (a) keep an incubator warm (b) start a fan when hot (c) switch on with a clap (d) stop a robot near walls
23. 23.Which job needs a temperature sensor? (a) spot someone walking in (b) open blinds at sunrise (c) close a window in rain (d) keep an incubator warm
24. 24.🔍 Which sensor would you use to close a window in rain? (a) a rain sensor (b) a sound sensor (c) a gas sensor (d) a light sensor
25. 25.Which job needs a servo motor? (a) show a status light (b) beep an alarm (c) spin a robot’s wheels (d) open a gate to 90°
26. 26.🔍 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)?
27. 27.🔍 Which sensor would you use to warn of a gas leak? (a) a distance sensor (b) a motion sensor (c) a temperature sensor (d) a gas sensor
28. 28.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a buzzer (c) a pump (d) a servo motor
29. 29.⚙️ Which actuator would you use to beep an alarm? (a) a display (b) an LED (c) a motor (d) a buzzer
30. 30.⚙️ Which actuator would you use to show a status light? (a) a pump (b) a servo motor (c) a motor (d) an LED
31. 31.Which job needs a display? (a) show a status light (b) open a gate to 90° (c) show the temperature (d) spin a robot’s wheels
32. 32.Which job needs a gas sensor? (a) start a fan when hot (b) make a parking alarm (c) warn of a gas leak (d) switch on lamps at dusk
33. 33.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
34. 34.🔍 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)?
35. 35.🔍 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)?
36. 36.True or false: to warn of a gas leak, use a sound sensor. (a) True (b) False
37. 37.🔍 A distance sensor sends a sound pulse and hears the echo 20 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
38. 38.Which job needs a pump? (a) open a gate to 90° (b) turn to an exact angle (c) beep an alarm (d) move water to plants
39. 39.⚙️ Which actuator would you use to spin a robot’s wheels? (a) an LED (b) a display (c) a buzzer (d) a motor
40. 40.🔍 An object is 136 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