Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 676 · 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.🤖 Microcontroller or laptop: which one runs one small program? (a) laptop (b) microcontroller
2. 2.Which drawing is the symbol for a resistor? (a) two equal parallel lines (b) triangle against a bar (c) a circle with A inside (d) a plain rectangle
3. 3.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
4. 4.⏱️ How many milliseconds is a wait of 3.6 seconds?
5. 5.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
6. 6.🔋 A 12 V battery and one 1.5 V cell are joined in series, all facing the same way. What is the total voltage (in volts)? =
7. 7.🧩 A capacitor in a circuit can … (a) spin a wheel (b) make light (c) store charge briefly (d) measure heat
8. 8.🔐 Is it a good or a risky habit to turn off unused gadgets? (a) good habit (b) risky habit
9. 9.🧮 Adding another resistor in series makes the total resistance … (a) smaller (b) stay the same (c) zero (d) bigger
10. 10.What does the microcontroller do? (a) carries the data (b) reads values, decides (c) stores data online (d) measures the real world
11. 11.Which of these uses electricity? (a) a bicycle dynamo (b) a power station (c) a battery (d) a computer
12. 12.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 HIGH
    set pin 7 LOW
    set pin 7 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
13. 13.Which of these is safe? (a) fly a kite near wires (b) use a cable with cuts (c) stay away from pylons (d) touch a switch when wet
14. 14.⏱️ A program says “wait 250 ms”. How many seconds is that? =
15. 15.Which of these is true of a series circuit? (a) each gets the full volts (b) own switch for each bulb (c) one bulb out, all go out (d) many paths for current
16. 16.🔘 Two switches are in series. When does the bulb glow? (a) when both are ON (b) when either is ON (c) when both are OFF (d) never
17. 17.🔍 Which is the odd one out? (a) a safety pin (b) a steel spoon (c) a woollen thread (d) a graphite rod
18. 18.🔋 Does an air conditioner give electricity or use electricity? (a) gives electricity (b) uses electricity
19. 19.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) by Wi-Fi (b) in parallel (c) in series (d) not joined
20. 20.🔁 total = 0
    for i = 1 to 4 { total = total + i }
    What is total at the end?
21. 21.True or false: to build with an adult near is safe. (a) False (b) True
22. 22.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
23. 23.💡 In a series circuit, how many paths does the current have? (a) none (b) one (c) two (d) one for each bulb
24. 24.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = I × R (c) V = R ÷ I (d) V = I ÷ R
25. 25.🔺 A current of 25 mA flows when 3 V is joined across a resistor. What is its resistance (in ohms)?
26. 26.Which of these is measured in volts (V)? (a) the flow of charge (b) the push of a cell (c) power (d) energy used each second
27. 27.🔌 Is aluminium foil a conductor or an insulator? (a) an insulator (b) a conductor
28. 28.🤖 if (temperature > 25) { fan ON } else { fan OFF }
    The temperature sensor reads 31 °C. What happens? (a) fan OFF (b) fan ON
29. 29.True or false: a traffic signal mainly gives out light. (a) False (b) True
30. 30.💡 A red LED uses 2 V and should get 10 mA. It runs from a 6 V supply. What resistor (in ohms) is needed in series?
31. 31.⚠️ Is it safe to poke things in a socket? (a) safe (b) not safe
32. 32.Which of these is the output? (a) check if temp > 30 (b) a motion sensor signal (c) decide if soil is dry (d) an LED lights up
33. 33.💡 3 identical bulbs are joined in series with a 12 V battery (ideal wires). How many volts does each bulb get? =
34. 34.Which of these is measured in ohms (Ω)? (a) energy used each second (b) voltage (c) the flow of charge (d) how much a part resists
35. 35.🔗 Series or parallel circuit: “own switch for each bulb”? (a) parallel (b) series
36. 36.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 900 ms }
    How many times does the LED blink in 3 seconds?
37. 37.✏️ In a circuit diagram, wires are usually drawn as … (a) dotted circles (b) straight lines (c) wavy lines (d) little stars
38. 38.🔋 What should you do with used-up cells? (a) bury them in soil (b) throw them in a fire (c) cut them open (d) give them for recycling
39. 39.True or false: on an LED, the longer leg is the cathode (−). (a) True (b) False
40. 40.🔘 Which kind of switch closes when tipped over? (a) a push button (b) a toggle switch (c) a tilt switch (d) a slide switch

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