Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 881 · 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 job needs a light sensor? (a) keep an incubator warm (b) switch on lamps at dusk (c) make a parking alarm (d) switch on with a clap
2. 2.⚡ Which formula gives electric power? (a) P = V + I (b) P = I ÷ V (c) P = V × I (d) P = V ÷ I
3. 3.🔺 A current of 1.5 A flows when 9 V is joined across a resistor. What is its resistance (in ohms)?
4. 4.🔺 A 3.3 V supply is joined across a 330 Ω resistor. What current flows (in milliamperes, mA)?
5. 5.What does a potentiometer do? (a) is a resistance knob (b) blows if current is high (c) has coloured bands (d) lets current go one way
6. 6.True or false: how much a part resists is measured in ohms (Ω). (a) False (b) True
7. 7.🔍 Which is the odd one out? (a) a water pump (b) a buzzer (c) an LED (d) a turning knob
8. 8.True or false: to cover unused cameras is a good habit. (a) False (b) True
9. 9.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) none (b) it does not matter (c) both of them (d) only one
10. 10.Which drawing is the symbol for a motor? (a) a circle with a cross (b) two or more cell symbols (c) a circle with M inside (d) triangle, bar and arrows
11. 11.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they keep glowing (c) they all go out (d) they get dimmer
12. 12.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
13. 13.⚠️ Is it safe to dry your hands first? (a) not safe (b) safe
14. 14.🔐 Privacy for a smart device means controlling … (a) its battery size (b) how loud it beeps (c) who can see your data (d) its colour
15. 15.True or false: aluminium foil is an insulator. (a) False (b) True
16. 16.True or false: a diode glows using little power. (a) False (b) True
17. 17.🔌 Is a glass marble a conductor or an insulator? (a) an insulator (b) a conductor
18. 18.🔌 Most metals are good … (a) magnets only (b) insulators (c) batteries (d) conductors
19. 19.True or false: “a tilt switch: on or off” is a digital signal. (a) True (b) False
20. 20.Which of these mainly makes movement? (a) a siren (b) a torch (c) a table fan (d) a school bell
21. 21.✏️ Why do engineers draw circuits with symbols? (a) quick and clear for all (b) to make it colourful (c) symbols are heavier (d) to hide the circuit
22. 22.🌈 In the resistor colour code, which number does brown stand for?
23. 23.True or false: to fly a kite near wires is safe. (a) False (b) True
24. 24.🔁 What does a variable do in a program? (a) blinks an LED (b) measures light (c) joins two wires (d) stores a value
25. 25.What does a transistor do? (a) boosts a small signal (b) stores a little charge (c) senses how hot it is (d) glows using little power
26. 26.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a ceramic cup. Does the bulb glow? (a) No (b) Yes
27. 27.True or false: an electric iron mainly gives out heat. (a) True (b) False
28. 28.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 220 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
29. 29.🔋 Does a battery give electricity or use electricity? (a) uses electricity (b) gives electricity
30. 30.🌈 A resistor has the colour bands white, red, brown. What is its value (in ohms)?
31. 31.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) stays the same (b) becomes zero (c) gets bigger (d) gets smaller
32. 32.💡 3 identical bulbs are joined in parallel across a 6 V battery (ideal wires). How many volts does each bulb get? =
33. 33.What does the microcontroller do? (a) carries the data (b) shows data to you (c) reads values, decides (d) measures the real world
34. 34.🌐 In an IoT system, which part reads values, decides? (a) microcontroller (b) Wi-Fi (c) phone app (d) sensor
35. 35.🤖 if (temperature > 36) { show “Hot” } else if (temperature > 22) { show “Warm” } else { show “Cool” }
    The temperature is 24 °C. What is shown? (a) Hot (b) Warm (c) Cool
36. 36.⚠️ Is it safe to climb an electric pole? (a) safe (b) not safe
37. 37.🔺 A 2.5 V supply is joined across a 250 Ω resistor. What current flows (in milliamperes, mA)?
38. 38.🔌 Which part of a screwdriver should an electrician hold? (a) the bare end (b) the plastic handle (c) the metal tip (d) the steel shaft
39. 39.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) the shorter line (c) neither line (d) the longer line
40. 40.🧩 A capacitor in a circuit can … (a) make light (b) measure heat (c) spin a wheel (d) store charge briefly

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