Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 175 · 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.🔍 An object is 85 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
2. 2.⚙️ What is an actuator? (a) an output that acts (b) a sensor (c) a battery (d) a program
3. 3.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a motor (c) a pump (d) a servo motor
4. 4.Which job needs a display? (a) show a status light (b) spin a robot’s wheels (c) show the temperature (d) move water to plants
5. 5.True or false: to start a fan when hot, use a temperature sensor. (a) True (b) False
6. 6.True or false: to spot someone walking in, use a rain sensor. (a) False (b) True
7. 7.⚙️ Which actuator would you use to beep an alarm? (a) a pump (b) a buzzer (c) a motor (d) a servo motor
8. 8.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a servo motor (b) a display (c) a motor (d) an LED
9. 9.True or false: to make a parking alarm, use a light sensor. (a) False (b) True
10. 10.Which job needs a temperature sensor? (a) switch on lamps at dusk (b) make a parking alarm (c) spot someone walking in (d) start a fan when hot
11. 11.True or false: to water a dry plant, use a light sensor. (a) True (b) False
12. 12.🔍 Which sensor would you use to spot someone walking in? (a) a soil moisture sensor (b) a motion sensor (c) a distance sensor (d) a rain sensor
13. 13.🔍 Which sensor would you use to switch on lamps at dusk? (a) a soil moisture sensor (b) a distance sensor (c) a motion sensor (d) a light sensor
14. 14.🔍 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?
15. 15.Which job needs a light sensor? (a) water a dry plant (b) keep an incubator warm (c) switch on lamps at dusk (d) spot someone walking in
16. 16.Which job needs an LED? (a) beep an alarm (b) show a status light (c) turn to an exact angle (d) show the temperature
17. 17.🔍 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?
18. 18.⚙️ Which actuator would you use to open a gate to 90°? (a) a servo motor (b) a display (c) an LED (d) a pump
19. 19.🔍 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?
20. 20.⚙️ Which actuator would you use to show a status light? (a) a servo motor (b) an LED (c) a pump (d) a buzzer
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.Which job needs a servo motor? (a) spin a robot’s wheels (b) show a status light (c) show the temperature (d) turn to an exact angle
23. 23.Which job needs a temperature sensor? (a) switch on lamps at dusk (b) measure classroom noise (c) keep an incubator warm (d) close a window in rain
24. 24.🔍 Which sensor would you use to stop a robot near walls? (a) a motion sensor (b) a rain sensor (c) a distance sensor (d) a temperature sensor
25. 25.Which job needs a servo motor? (a) spin a robot’s wheels (b) show a status light (c) show the temperature (d) open a gate to 90°
26. 26.🔍 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)?
27. 27.🔍 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?
28. 28.True or false: to measure classroom noise, use a sound sensor. (a) True (b) False
29. 29.Which job needs a sound sensor? (a) water a dry plant (b) spot someone walking in (c) warn of a gas leak (d) measure classroom noise
30. 30.Which job needs a buzzer? (a) show a status light (b) beep an alarm (c) move water to plants (d) spin a robot’s wheels
31. 31.🔍 A distance sensor sends a sound pulse and hears the echo 18 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
32. 32.True or false: to make a parking alarm, use a sound sensor. (a) False (b) True
33. 33.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
34. 34.Which job needs a light sensor? (a) spot someone walking in (b) stop a robot near walls (c) start a fan when hot (d) open blinds at sunrise
35. 35.True or false: to water a dry plant, use a soil moisture sensor. (a) True (b) False
36. 36.True or false: to stop a robot near walls, use a distance sensor. (a) False (b) True
37. 37.Which job needs a gas sensor? (a) open blinds at sunrise (b) warn of a gas leak (c) water a dry plant (d) switch on with a clap
38. 38.Which job needs a motion sensor? (a) spot someone walking in (b) close a window in rain (c) switch on with a clap (d) water a dry plant
39. 39.🔍 An object is 340 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
40. 40.True or false: to measure classroom noise, use a distance sensor. (a) False (b) True

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