Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 923 · 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 band is read first on a resistor? (a) the gold band (b) the widest gap (c) the one nearest an end (d) any band
2. 2.🧮 Five equal 50 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
3. 3.🔍 Which is the odd one out? (a) a plastic ruler (b) a safety pin (c) a rubber eraser (d) a woollen thread
4. 4.📏 How many milliamperes (mA) is 2.33 A?
5. 5.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 50 ms }
   How many times does the LED blink in 6 seconds?
6. 6.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
7. 7.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) switch (b) motor (c) diode (d) ammeter
8. 8.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they all go out (b) they get dimmer (c) they keep glowing (d) they explode
9. 9.🔺 A current of 1 A flows through a 15 Ω resistor. What is the voltage across it (in volts)? =
10. 10.Which of these is not safe? (a) dry your hands first (b) open a phone charger (c) stay away from pylons (d) build with an adult near
11. 11.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
12. 12.True or false: if a wire has come loose, the circuit is open and no current flows. (a) True (b) False
13. 13.🤖 How does a new program get onto a microcontroller board? (a) drawn with a pen (b) typed on the chip (c) sent by sound (d) uploaded over USB
14. 14.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) series (b) parallel
15. 15.Which of these is true of a series circuit? (a) used in house wiring (b) a break stops every bulb (c) many paths for current (d) one out, the rest glow
16. 16.🌐 In an IoT system, which part acts on a command? (a) microcontroller (b) actuator (c) Wi-Fi (d) sensor
17. 17.⏱️ A program says “wait 3250 ms”. How many seconds is that? =
18. 18.🔺 A 3 V supply is joined across a 150 Ω resistor. What current flows (in milliamperes, mA)?
19. 19.Which of these is an IoT device? (a) a Wi-Fi smart plug (b) a plain wall switch (c) a paper calendar (d) a pencil sharpener
20. 20.✏️ In a circuit diagram, which part is drawn as a circle with A inside? (a) ammeter (b) diode (c) switch (d) battery
21. 21.True or false: a circle with V inside is the symbol for a capacitor. (a) True (b) False
22. 22.🔁 What does “count = count + 1” do? (a) sets count to 1 (b) prints 1 (c) takes 1 away (d) adds 1 to count
23. 23.💡 Why is house wiring done in parallel? (a) to make bulbs dim (b) to save copper only (c) so all go off together (d) each gets full voltage
24. 24.Which of these is an output? (a) a light sensor (b) a small display (c) a sound sensor (d) a temperature sensor
25. 25.🔐 Is it a good or a risky habit to cover unused cameras? (a) good habit (b) risky habit
26. 26.🤖 Microcontroller or laptop: which one has no screen of its own? (a) laptop (b) microcontroller
27. 27.⏱️ repeat 7 times { buzzer ON; wait 300 ms; buzzer OFF; wait 700 ms }
    How many milliseconds does this take in all?
28. 28.Which of these is a good habit? (a) share the Wi-Fi key (b) ignore update messages (c) set up with a parent (d) keep factory passwords
29. 29.Which of these is a good habit? (a) keep factory passwords (b) share camera links (c) ignore update messages (d) install software updates
30. 30.🔗 Series or parallel circuit: “used in house wiring”? (a) series (b) parallel
31. 31.📏 In the water-pipe picture of a circuit, voltage is like … (a) the pipe colour (b) the tap handle (c) the water pressure (d) the water tank lid
32. 32.⚡ A 1.5 W device works on 3 V. What current does it take (in amperes)? =
33. 33.✏️ In a cell symbol, which line is the + terminal? (a) the shorter line (b) the longer line (c) neither line (d) both lines
34. 34.True or false: on an LED, the round-side leg is the anode (+). (a) False (b) True
35. 35.⚡ A 0.15 W device works on 1.5 V. What current does it take (in amperes)? =
36. 36.True or false: on a cell, “the flat end” means the + (positive) end. (a) False (b) True
37. 37.Which of these is an input? (a) a speaker (b) a water pump (c) a temperature sensor (d) a small display
38. 38.🤖 if (distance < 20) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 23 cm. What happens? (a) buzzer beeps (b) buzzer is silent
39. 39.🔺 A current of 40 mA flows through a 250 Ω resistor. What is the voltage across it (in volts)? =
40. 40.True or false: to switch off empty rooms saves electricity. (a) True (b) False

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