Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 723 · 40 questions

Remember (Find the topic, use the idea): Find the topic: circuit, safety, formula, component, program, sensor or IoT. Use that lesson’s rule — complete loop, V = I × R, P = V × I, last command wins, true → if part. Safety answers are always: low voltage, dry hands, an adult, never the mains.

1. 1.✏️ Why do engineers draw circuits with symbols? (a) symbols are heavier (b) quick and clear for all (c) to hide the circuit (d) to make it colourful
2. 2.🔍 Which is the odd one out? (a) unplug idle chargers (b) switch off empty rooms (c) leave the TV on standby (d) use LED lamps
3. 3.🔍 Which is the odd one out? (a) a sound sensor (b) a push button (c) a speaker (d) a motion sensor
4. 4.🔍 Which is the odd one out? (a) climb an electric pole (b) stop if a part gets hot (c) use small battery cells (d) keep drinks far away
5. 5.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 5 minutes?
6. 6.🌐 Each reading a sensor sends is 50 bytes. How many bytes do 120 readings take?
7. 7.🔐 Is it a good or a risky habit to install software updates? (a) risky habit (b) good habit
8. 8.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
9. 9.Which of these means the circuit is open? (a) the loop is complete (b) the switch is ON (c) all wires are joined (d) a wire has come loose
10. 10.💡 4 identical bulbs are joined in parallel across a 1.5 V battery (ideal wires). How many volts does each bulb get? =
11. 11.Which of these wastes electricity? (a) iron one shirt at a time (b) use daylight to read (c) set the AC to 24 °C (d) close the fridge quickly
12. 12.True or false: a laptop has no screen of its own. (a) True (b) False
13. 13.What does a fuse do? (a) makes a beeping sound (b) boosts a small signal (c) blows if current is high (d) is a resistance knob
14. 14.⚡ A 36 W device works on 24 V. What current does it take (in amperes)? =
15. 15.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) + (positive) (b) − (negative)
16. 16.🔍 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?
17. 17.🔐 Is it a good or a risky habit to read app permissions? (a) good habit (b) risky habit
18. 18.What does a toggle switch do? (a) closes near a magnet (b) slides side to side (c) stays where you flip it (d) works only while pressed
19. 19.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they get dimmer (c) they all go out (d) they keep glowing
20. 20.🤖 Microcontroller or laptop: which one needs much more power? (a) laptop (b) microcontroller
21. 21.🔁 repeat 2 times { repeat 2 times { beep } }
    How many beeps are there?
22. 22.💡 A battery lights 3 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) dimmer (c) brighter
23. 23.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) put it in the bathroom (b) tell it your passwords (c) let strangers use it (d) mute it when not in use
24. 24.Which of these is an output? (a) a motion sensor (b) a water pump (c) a temperature sensor (d) a push button
25. 25.🔌 Is a keypad an input or an output for a microcontroller? (a) input (b) output
26. 26.⚡ What does an electric toy car mainly change electricity into? (a) movement (b) sound (c) light (d) heat
27. 27.🔌 Which part of a screwdriver should an electrician hold? (a) the metal tip (b) the steel shaft (c) the bare end (d) the plastic handle
28. 28.🤖 if (temperature > 34) { show “Hot” } else if (temperature > 24) { show “Warm” } else { show “Cool” }
    The temperature is 18 °C. What is shown? (a) Cool (b) Warm (c) Hot
29. 29.🔘 Which kind of switch springs back when let go? (a) a push button (b) a reed switch (c) a toggle switch (d) a tilt switch
30. 30.True or false: a steel coin is a conductor. (a) False (b) True
31. 31.True or false: on a cell, “the end with a bump” means the − (negative) end. (a) True (b) False
32. 32.📶 Digital or analog: how loud a sound is? (a) digital (b) analog
33. 33.📶 Digital or analog: HIGH or LOW only? (a) analog (b) digital
34. 34.Which of these is the process? (a) a soil moisture reading (b) decide if soil is dry (c) an LED lights up (d) a motion sensor signal
35. 35.🧩 Which component is a resistance knob? (a) motor (b) LED (c) LDR (d) potentiometer
36. 36.True or false: “count button presses” is the process. (a) True (b) False
37. 37.Which of these is the input? (a) a temperature reading (b) count button presses (c) an LED lights up (d) check if temp > 30
38. 38.🧭 Which part of a microcontroller board keeps the voltage steady? (a) the power LED (b) the reset button (c) the voltage regulator (d) the pins
39. 39.🔢 To run one loop of a plant-watering program, which is the FIRST step? (a) read the soil sensor (b) switch the pump on/off (c) compare with the limit (d) wait a few seconds
40. 40.Which of these means the circuit is closed? (a) a wire has come loose (b) the loop is complete (c) the switch is OFF (d) the bulb is unscrewed

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