Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 722 · 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.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a ceramic cup across the gap. Does the bulb glow? (a) Yes (b) No
2. 2.🌐 A weather station sends one reading every 15 seconds. How many readings does it send in 10 minutes?
3. 3.🔋 How many volts does one ordinary torch cell give? (a) 15 V (b) 0.5 V (c) 230 V (d) 1.5 V
4. 4.🧮 Five equal 50 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
5. 5.🌈 Which band is read first on a resistor? (a) the gold band (b) the widest gap (c) the one nearest an end (d) any band
6. 6.⚙️ What is an actuator? (a) an output that acts (b) a sensor (c) a battery (d) a program
7. 7.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the base (b) the glass (c) the switch (d) the filament
8. 8.🔁 What does a variable do in a program? (a) joins two wires (b) stores a value (c) measures light (d) blinks an LED
9. 9.🧩 Which component stores a little charge? (a) resistor (b) LED (c) capacitor (d) motor
10. 10.Which of these wastes electricity? (a) unplug idle chargers (b) switch off empty rooms (c) use daylight to read (d) leave fridge door open
11. 11.Which drawing is the symbol for a diode? (a) a plain rectangle (b) triangle against a bar (c) a small empty box (d) two or more cell symbols
12. 12.📏 Which unit measures voltage? (a) ohm (Ω) (b) watt (W) (c) ampere (A) (d) volt (V)
13. 13.🏠 Which is a smart-home example? (a) lights on from an app (b) a hand fan (c) a printed map (d) a candle in a jar
14. 14.💡 In a series circuit, how many paths does the current have? (a) none (b) two (c) one (d) one for each bulb
15. 15.🧮 Adding another resistor in series makes the total resistance … (a) stay the same (b) bigger (c) smaller (d) zero
16. 16.⚡ What does a tube light mainly change electricity into? (a) sound (b) movement (c) heat (d) light
17. 17.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is OFF, B is OFF and C is OFF. Does the bulb glow? (a) Yes (b) No
18. 18.True or false: “one out, the rest glow” is true of a series circuit. (a) True (b) False
19. 19.Which of these is a good habit? (a) accept every permission (b) post your live location (c) share the Wi-Fi key (d) read app permissions
20. 20.📏 Voltmeter or ammeter: which one measures voltage? (a) ammeter (b) voltmeter
21. 21.🧾 A 1000 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
22. 22.🔺 A current of 20 mA flows when 3 V is joined across a resistor. What is its resistance (in ohms)?
23. 23.✏️ In a circuit diagram, which part is drawn as a dot where wires meet? (a) battery (b) capacitor (c) cell (d) junction
24. 24.True or false: an electric drill mainly makes movement. (a) True (b) False
25. 25.🔍 Which sensor would you use to switch on lamps at dusk? (a) a soil moisture sensor (b) a rain sensor (c) a temperature sensor (d) a light sensor
26. 26.💡 3 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. Bulb 1 is taken out of its holder. How many bulbs glow?
27. 27.🔢 To run one loop of a plant-watering program, what comes right after “switch the pump on/off”? (a) read the soil sensor (b) wait a few seconds (c) compare with the limit
28. 28.Which of these means the circuit is closed? (a) a wire is cut (b) a wire has come loose (c) the bulb is unscrewed (d) all wires are joined
29. 29.🔁 count = 5
    while (count < 20) { count = count + 5 }
    How many times does the loop run?
30. 30.💡 A battery lights 4 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) brighter (c) the same
31. 31.True or false: a wooden stick is a conductor. (a) True (b) False
32. 32.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = I ÷ V (c) P = V × I (d) P = V + I
33. 33.🧮 A 7 V battery is joined to 10 Ω and 4 Ω resistors in series. What current flows (in amperes)? =
34. 34.💡 Why is house wiring done in parallel? (a) so all go off together (b) each gets full voltage (c) to save copper only (d) to make bulbs dim
35. 35.🌐 Each reading a sensor sends is 20 bytes. How many bytes do 40 readings take?
36. 36.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) symbols are heavier (c) to hide the circuit (d) quick and clear for all
37. 37.True or false: on an LED, the round-side leg is the cathode (−). (a) True (b) False
38. 38.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they all go out (c) they keep glowing (d) they get dimmer
39. 39.🔺 A 10 V supply is joined across a 250 Ω resistor. What current flows (in milliamperes, mA)?
40. 40.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)

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