Electronics Worksheet: Sensors and Actuators

Electronics lesson 26: Sensors and actuators · Set 316 · 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 sensor would you use to measure classroom noise? (a) a light sensor (b) a temperature sensor (c) a sound sensor (d) a motion sensor
3. 3.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) an input (c) a power source (d) a fuse
4. 4.🔍 Which sensor would you use to warn of a gas leak? (a) a light sensor (b) a gas sensor (c) a distance sensor (d) a motion sensor
5. 5.🔍 An object is 272 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
6. 6.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a servo motor (b) a display (c) a buzzer (d) a motor
7. 7.🔍 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)?
8. 8.⚙️ Which actuator would you use to open a gate to 90°? (a) a pump (b) a buzzer (c) an LED (d) a servo motor
9. 9.Which job needs a temperature sensor? (a) keep an incubator warm (b) measure classroom noise (c) close a window in rain (d) switch on lamps at dusk
10. 10.🔍 Which sensor would you use to water a dry plant? (a) a temperature sensor (b) a light sensor (c) a soil moisture sensor (d) a distance sensor
11. 11.⚙️ What is an actuator? (a) a sensor (b) an output that acts (c) a program (d) a battery
12. 12.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a pump (c) a servo motor (d) a display
13. 13.Which job needs a gas sensor? (a) open blinds at sunrise (b) water a dry plant (c) start a fan when hot (d) warn of a gas leak
14. 14.Which job needs a motion sensor? (a) switch on lamps at dusk (b) water a dry plant (c) close a window in rain (d) spot someone walking in
15. 15.Which job needs a distance sensor? (a) keep an incubator warm (b) start a fan when hot (c) spot someone walking in (d) make a parking alarm
16. 16.Which job needs an LED? (a) turn to an exact angle (b) show a status light (c) move water to plants (d) spin a robot’s wheels
17. 17.True or false: to keep an incubator warm, use a gas sensor. (a) True (b) False
18. 18.⚙️ Which actuator would you use to beep an alarm? (a) a buzzer (b) a servo motor (c) a pump (d) a display
19. 19.Which job needs a light sensor? (a) switch on lamps at dusk (b) stop a robot near walls (c) warn of a gas leak (d) water a dry plant
20. 20.🔍 An object is 323 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
21. 21.Which job needs a servo motor? (a) turn to an exact angle (b) show the temperature (c) show a status light (d) spin a robot’s wheels
22. 22.True or false: to warn of a gas leak, use a distance sensor. (a) True (b) False
23. 23.🔍 A distance sensor sends a sound pulse and hears the echo 19 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
24. 24.True or false: to stop a robot near walls, use a rain sensor. (a) False (b) True
25. 25.Which job needs a sound sensor? (a) measure classroom noise (b) keep an incubator warm (c) switch on lamps at dusk (d) start a fan when hot
26. 26.🔍 Which sensor would you use to spot someone walking in? (a) a sound sensor (b) a rain sensor (c) a motion sensor (d) a distance sensor
27. 27.🔍 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?
28. 28.True or false: to close a window in rain, use a light sensor. (a) True (b) False
29. 29.Which job needs a rain sensor? (a) close a window in rain (b) keep an incubator warm (c) measure classroom noise (d) switch on lamps at dusk
30. 30.Which job needs a servo motor? (a) spin a robot’s wheels (b) show a status light (c) move water to plants (d) open a gate to 90°
31. 31.⚙️ Which actuator would you use to show a status light? (a) an LED (b) a motor (c) a pump (d) a display
32. 32.True or false: to spot someone walking in, use a motion sensor. (a) False (b) True
33. 33.🔍 Which sensor would you use to keep an incubator warm? (a) a temperature sensor (b) a light sensor (c) a sound sensor (d) a motion sensor
34. 34.🔍 Which sensor would you use to open blinds at sunrise? (a) a light sensor (b) a distance sensor (c) a gas sensor (d) a motion sensor
35. 35.🔍 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)?
36. 36.🔍 Which sensor would you use to stop a robot near walls? (a) a distance sensor (b) a sound sensor (c) a soil moisture sensor (d) a rain sensor
37. 37.True or false: to switch on with a clap, use a light sensor. (a) False (b) True
38. 38.Which job needs a display? (a) show a status light (b) open a gate to 90° (c) show the temperature (d) turn to an exact angle
39. 39.True or false: to open blinds at sunrise, use a soil moisture sensor. (a) False (b) True
40. 40.🔍 An object is 119 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?

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