Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 610 · 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.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 3 is taken out of its holder. Does bulb 2 glow? (a) Yes (b) No
2. 2.True or false: if the loop is complete, the circuit is closed and current flows. (a) False (b) True
3. 3.💡 What happens if an LED is put in backwards? (a) it lights brighter (b) it does not light (c) it changes colour (d) it makes a sound
4. 4.🗺️ Before building a project, what should you write down first? (a) nothing at all (b) the box colour (c) the final price (d) inputs and outputs
5. 5.What does the phone app do? (a) stores data online (b) shows data to you (c) carries the data (d) reads values, decides
6. 6.⚠️ Is it safe to touch a switch when wet? (a) safe (b) not safe
7. 7.True or false: if a cell is taken out, the circuit is open and no current flows. (a) True (b) False
8. 8.⚡ A 48 W device works on 24 V. What current does it take (in amperes)? =
9. 9.🧩 Which component smooths a wobbly supply? (a) potentiometer (b) capacitor (c) transistor (d) LDR
10. 10.Which of these means the circuit is open? (a) the switch is ON (b) all wires are joined (c) the loop is complete (d) a wire is cut
11. 11.🌐 In an IoT system, which part acts on a command? (a) microcontroller (b) actuator (c) sensor (d) phone app
12. 12.⏱️ A program says “wait 7750 ms”. How many seconds is that? =
13. 13.🔘 A cell, a bulb and switches A, B and C are joined one after another in a single loop (series). A is OFF, B is ON and C is ON. Does the bulb glow? (a) No (b) Yes
14. 14.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) True (b) False
15. 15.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) − (negative) (b) + (positive)
16. 16.Which of these is measured in volts (V)? (a) how much a part resists (b) the push of a cell (c) current (d) the flow of charge
17. 17.🤖 Microcontroller or laptop: which one has a built-in keyboard? (a) laptop (b) microcontroller
18. 18.💡 5 identical bulbs are in parallel and each bulb has its own switch on its path. 1 of the switches is OFF and the rest are ON. How many bulbs glow?
19. 19.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
20. 20.⚡ What do we call a flow of electric charge through a wire? (a) friction (b) sound (c) electric current (d) a magnet
21. 21.🔘 Which kind of switch works only while pressed? (a) a toggle switch (b) a slide switch (c) a reed switch (d) a push button
22. 22.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) turns the LED off (c) blinks 500 times (d) pauses for half a second
23. 23.🔺 A current of 20 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
24. 24.Which of these is safe? (a) fly a kite near wires (b) throw cells in a fire (c) stop if a part gets hot (d) open a phone charger
25. 25.🔍 Which is the odd one out? (a) use daylight to read (b) use LED lamps (c) set the AC to 24 °C (d) leave the TV on standby
26. 26.🔁 x = 1
    repeat 5 times { x = x × 2 }
    What is x at the end?
27. 27.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) the shorter line (c) the longer line (d) neither line
28. 28.Which of these usually has a microcontroller inside? (a) a bicycle bell (b) a plain wall switch (c) a hand pump (d) a digital alarm clock
29. 29.True or false: “how loud a sound is” is an analog signal. (a) True (b) False
30. 30.🔺 A current of 50 mA flows through a 200 Ω resistor. What is the voltage across it (in volts)? =
31. 31.True or false: on an LED, the shorter leg is the cathode (−). (a) True (b) False
32. 32.🔍 Which is the odd one out? (a) check if temp > 30 (b) a soil moisture reading (c) compare with a limit (d) count button presses
33. 33.Which of these mainly gives out light? (a) an electric iron (b) a school bell (c) a rice cooker (d) a torch
34. 34.📶 Digital or analog: HIGH or LOW only? (a) analog (b) digital
35. 35.🔁 x = 4
    repeat 4 times { x = x × 2 }
    What is x at the end?
36. 36.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
37. 37.🔋 What is a battery? (a) a kind of bulb (b) one single wire (c) two or more cells joined (d) a switch with a lid
38. 38.⚡ Which formula gives electric power? (a) P = I ÷ V (b) P = V × I (c) P = V ÷ I (d) P = V + I
39. 39.🔘 Which kind of switch springs back when let go? (a) a toggle switch (b) a push button (c) a slide switch (d) a tilt switch
40. 40.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the glass (b) the switch (c) the filament (d) the base

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