Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 674 · 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.🔍 Which is the odd one out? (a) a steel spoon (b) a ceramic cup (c) a wooden stick (d) a dry cork
2. 2.🔌 Is a cotton thread a conductor or an insulator? (a) a conductor (b) an insulator
3. 3.True or false: a capacitor stores a little charge. (a) True (b) False
4. 4.True or false: to accept every permission is a good habit. (a) True (b) False
5. 5.🔺 A 10 V supply is joined across a 250 Ω resistor. What current flows (in milliamperes, mA)?
6. 6.🔍 Which is the odd one out? (a) iron one shirt at a time (b) use old filament bulbs (c) use daylight to read (d) leave the TV on standby
7. 7.💡 A battery lights 2 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) the same (b) dimmer (c) brighter
8. 8.Which of these is a conductor? (a) a paper strip (b) aluminium foil (c) a glass marble (d) a rubber eraser
9. 9.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
10. 10.💡 4 identical bulbs are in parallel and each bulb has its own switch on its path. 3 of the switches are OFF and the rest are ON. How many bulbs glow?
11. 11.🤖 Does a microwave oven usually have a microcontroller inside? (a) Yes (b) No
12. 12.Which of these means the circuit is closed? (a) the switch is ON (b) the bulb is unscrewed (c) a wire is cut (d) a wire has come loose
13. 13.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 2 is taken out of its holder. Does bulb 3 glow? (a) Yes (b) No
14. 14.⚡ A device works on 5 V and takes 1.5 A. What is its power (in watts)? =
15. 15.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 8 LOW
    set pin 7 LOW
    set pin 8 LOW
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
16. 16.True or false: triangle against a bar is the symbol for a diode. (a) True (b) False
17. 17.💡 2 identical bulbs are joined in parallel across a 6 V battery (ideal wires). How many volts does each bulb get? =
18. 18.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 2 hours. How many watt-hours (Wh) are saved?
19. 19.Which of these wastes electricity? (a) use LED lamps (b) use daylight to read (c) leave fridge door open (d) switch off empty rooms
20. 20.🔢 To run one loop of a plant-watering program, which is the FIRST step? (a) compare with the limit (b) wait a few seconds (c) read the soil sensor (d) switch the pump on/off
21. 21.🤖 Microcontroller or laptop: which one runs many apps at once? (a) microcontroller (b) laptop
22. 22.⚡ Power tells us … (a) the colour of light (b) the length of a wire (c) energy used each second (d) the size of a cell
23. 23.🌈 In the resistor colour code, which number does green stand for?
24. 24.🔍 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)?
25. 25.True or false: the flow of charge is measured in amperes (A). (a) False (b) True
26. 26.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 100 (c) 60 (d) 1000
27. 27.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 100 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
28. 28.True or false: to set the AC to 24 °C saves electricity. (a) False (b) True
29. 29.Which of these means the circuit is open? (a) the loop is complete (b) a wire has come loose (c) the switch is ON (d) all wires are joined
30. 30.🤖 Does a washing machine usually have a microcontroller inside? (a) Yes (b) No
31. 31.🔢 To plan an electronics project, which is the FIRST step? (a) draw the circuit diagram (b) list inputs and outputs (c) pick a problem to solve (d) build it with an adult
32. 32.🔍 Which is the odd one out? (a) touch a fallen wire (b) use mains for a project (c) dry your hands first (d) touch a switch when wet
33. 33.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 440 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
34. 34.True or false: “many paths for current” is true of a parallel circuit. (a) False (b) True
35. 35.What does a buzzer do? (a) smooths a wobbly supply (b) makes things spin (c) boosts a small signal (d) beeps for an alarm
36. 36.True or false: “each gets the full volts” is true of a parallel circuit. (a) False (b) True
37. 37.True or false: on a cell, “usually the black wire” means the + (positive) end. (a) False (b) True
38. 38.⚡ A device works on 9 V and takes 0.2 A. What is its power (in watts)? =
39. 39.Which of these is a good habit? (a) keep factory passwords (b) ignore update messages (c) share only needed data (d) share the Wi-Fi key
40. 40.🔁 count = 2
    repeat 3 times { count = count + 2 }
    What is count at the end?

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