Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 532 · 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.True or false: to open blinds at sunrise, use a light sensor. (a) False (b) True
2. 2.⚡ A device works on 1.5 V and takes 0.2 A. What is its power (in watts)? =
3. 3.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a glass marble across the gap. Does the bulb glow? (a) No (b) Yes
4. 4.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
   The light reading is 250 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
5. 5.Which of these is safe? (a) dry your hands first (b) touch a switch when wet (c) poke things in a socket (d) touch a fallen wire
6. 6.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) True (b) False
7. 7.🔢 To get a sensor reading onto a phone, what comes right after “the sensor measures”? (a) the app shows it (b) it is sent by Wi-Fi (c) the cloud stores it (d) the board reads it
8. 8.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a cotton thread. Does the bulb glow? (a) No (b) Yes
9. 9.True or false: a small empty box is the symbol for a capacitor. (a) True (b) False
10. 10.True or false: a slide switch slides side to side. (a) True (b) False
11. 11.🔐 Is it a good or a risky habit to cover unused cameras? (a) good habit (b) risky habit
12. 12.🔘 Which kind of switch works only while pressed? (a) a tilt switch (b) a slide switch (c) a push button (d) a reed switch
13. 13.🔋 How many 1.5 V cells must be joined in series to give 9 V?
14. 14.Which of these is true of a series circuit? (a) own switch for each bulb (b) many paths for current (c) a break stops every bulb (d) one out, the rest glow
15. 15.🤖 if (sound > 60) { red LED ON } else { green LED ON }
    The sound sensor reads 71. What happens? (a) red LED ON (b) green LED ON
16. 16.⚡ A 2.4 W device works on 24 V. What current does it take (in amperes)? =
17. 17.🧩 Which component blows if current is high? (a) potentiometer (b) capacitor (c) fuse (d) thermistor
18. 18.Which of these is true of a series circuit? (a) one bulb out, all go out (b) many paths for current (c) one out, the rest glow (d) own switch for each bulb
19. 19.🔢 To run one loop of a plant-watering program, which is the LAST step? (a) switch the pump on/off (b) compare with the limit (c) wait a few seconds (d) read the soil sensor
20. 20.Which of these means the circuit is open? (a) all wires are joined (b) a cell is taken out (c) the switch is ON (d) the loop is complete
21. 21.Which of these is not safe? (a) use small battery cells (b) use mains for a project (c) keep drinks far away (d) dry your hands first
22. 22.🧮 Five equal 25 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
23. 23.Which of these means the circuit is closed? (a) the switch is OFF (b) a wire is cut (c) the loop is complete (d) the bulb is unscrewed
24. 24.True or false: the voltmeter is joined across a part. (a) False (b) True
25. 25.🔁 Is the circuit closed or open if a wire is cut? (a) closed (b) open
26. 26.🔍 Which is the odd one out? (a) a table fan (b) an exhaust fan (c) a buzzer (d) an electric drill
27. 27.🌐 In an IoT system, which part shows data to you? (a) microcontroller (b) sensor (c) Wi-Fi (d) phone app
28. 28.True or false: a motor turns a fan or wheels. (a) False (b) True
29. 29.🌈 In the resistor colour code, which number does orange stand for?
30. 30.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
31. 31.True or false: “compare with a limit” is the process. (a) False (b) True
32. 32.🔁 repeat 3 times { repeat 4 times { beep } }
    How many beeps are there?
33. 33.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 950 ms }
    How many times does the LED blink in 3 seconds?
34. 34.🗺️ In an input → process → output plan, is “a light level reading” the input, the process or the output? (a) process (b) output (c) input
35. 35.🔺 A current of 1 A flows when 20 V is joined across a resistor. What is its resistance (in ohms)?
36. 36.🔢 To plan an electronics project, which is the FIRST step? (a) list inputs and outputs (b) pick a problem to solve (c) build it with an adult (d) draw the circuit diagram
37. 37.What does a toggle switch do? (a) flips up or down (b) slides side to side (c) closes when tipped over (d) works only while pressed
38. 38.🌐 How does a home IoT device usually send its data to the app? (a) by shouting (b) over Wi-Fi (c) through a candle (d) by post
39. 39.Which of these means the circuit is closed? (a) a cell is taken out (b) all wires are joined (c) a wire is cut (d) a wire has come loose
40. 40.💡 Why is house wiring done in parallel? (a) so all go off together (b) to make bulbs dim (c) to save copper only (d) each gets full voltage

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