Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 235 · 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 of these is an IoT device? (a) a wind-up clock (b) a Wi-Fi smart plug (c) a battery torch (d) a plain table fan
2. 2.⚡ A device works on 9 V and takes 1 A. What is its power (in watts)? =
3. 3.Which of these usually has a microcontroller inside? (a) a plain wall switch (b) a toy robot (c) a hand pump (d) a candle
4. 4.🤖 Microcontroller or laptop: which one has a built-in keyboard? (a) laptop (b) microcontroller
5. 5.🔢 To run one loop of a plant-watering program, which is the LAST step? (a) read the soil sensor (b) switch the pump on/off (c) compare with the limit (d) wait a few seconds
6. 6.🔢 To plan an electronics project, which comes first: “build it with an adult” or “draw the circuit diagram”? (a) build it with an adult (b) draw the circuit diagram
7. 7.🌈 In the resistor colour code, which number does white stand for?
8. 8.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) parallel (b) series
9. 9.🤖 “if (A AND B)” is true when … (a) both A and B are true (b) only B is true (c) only A is true (d) both are false
10. 10.🧾 A 250 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
11. 11.⏱️ How many milliseconds are in 1 second? (a) 1000 (b) 10 (c) 100 (d) 60
12. 12.💡 A blue LED uses 3 V and should get 20 mA. It runs from a 5 V supply. What resistor (in ohms) is needed in series?
13. 13.🤖 if (temperature > 38) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
    The temperature is 23 °C. What is shown? (a) Cool (b) Warm (c) Hot
14. 14.🤖 if (moisture < 40) { pump ON } else { pump OFF }
    The soil moisture sensor reads 25 %. What happens? (a) pump OFF (b) pump ON
15. 15.🔦 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 copper wire. Does the bulb glow? (a) No (b) Yes
16. 16.🔁 What does a variable do in a program? (a) measures light (b) joins two wires (c) blinks an LED (d) stores a value
17. 17.⏱️ loop forever { LED ON; wait 350 ms; LED OFF; wait 650 ms }
    How many times does the LED blink in 4 seconds?
18. 18.🔍 Which is the odd one out? (a) a plain table fan (b) a Wi-Fi smart plug (c) a battery torch (d) a wind-up clock
19. 19.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) straight lines (c) wavy lines (d) dotted circles
20. 20.🔍 Which is the odd one out? (a) dry your hands first (b) use small battery cells (c) poke things in a socket (d) fly kites in open fields
21. 21.True or false: on a cell, “the shorter symbol line” means the − (negative) end. (a) True (b) False
22. 22.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the output (b) the process (c) the battery (d) the input
23. 23.True or false: on a cell, “usually the black wire” means the − (negative) end. (a) True (b) False
24. 24.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the switch (b) the base (c) the filament (d) the glass
25. 25.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 750 ms }
    How many milliseconds does one blink (ON + OFF) take?
26. 26.📏 Voltmeter or ammeter: which one is joined in series? (a) ammeter (b) voltmeter
27. 27.True or false: a reed switch closes when tipped over. (a) False (b) True
28. 28.Which of these has no microcontroller inside? (a) a digital alarm clock (b) a digital thermometer (c) a TV remote (d) a hand pump
29. 29.📏 Which unit measures the flow of charge? (a) ohm (Ω) (b) volt (V) (c) watt (W) (d) ampere (A)
30. 30.True or false: voltage is measured in volts (V). (a) False (b) True
31. 31.🔺 A current of 50 mA flows through a 500 Ω resistor. What is the voltage across it (in volts)? =
32. 32.🔘 Which kind of switch springs back when let go? (a) a toggle switch (b) a slide switch (c) a reed switch (d) a push button
33. 33.Which drawing is the symbol for a resistor? (a) a straight line (b) a dot where wires meet (c) a plain rectangle (d) a long and a short line
34. 34.🔢 To get a sensor reading onto a phone, which comes first: “it is sent by Wi-Fi” or “the sensor measures”? (a) the sensor measures (b) it is sent by Wi-Fi
35. 35.🔁 Is the circuit closed or open if a cell is taken out? (a) closed (b) open
36. 36.🔘 Which kind of switch slides side to side? (a) a slide switch (b) a push button (c) a reed switch (d) a toggle switch
37. 37.🔌 Is a speaker an input or an output for a microcontroller? (a) output (b) input
38. 38.⚡ A 2.5 W device works on 5 V. What current does it take (in amperes)? =
39. 39.🔁 repeat 3 times { repeat 6 times { beep } }
    How many beeps are there?
40. 40.🔘 A cell and a bulb are joined to 4 side-by-side paths with one switch on each path — A, B, C and D (parallel). A is OFF, B is OFF, C is OFF and D is OFF. Does the bulb glow? (a) Yes (b) No

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