Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 433 · 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.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 8 HIGH
   set pin 7 HIGH
   set pin 7 LOW
   set pin 8 HIGH
   set pin 7 HIGH
   Is the LED ON or OFF at the end? (a) OFF (b) ON
2. 2.✏️ In a cell symbol, which line is the + terminal? (a) the shorter line (b) neither line (c) the longer line (d) both lines
3. 3.⚡ Which formula gives electric power? (a) P = V × I (b) P = V ÷ I (c) P = V + I (d) P = I ÷ V
4. 4.🔍 Which is the odd one out? (a) use a cable with cuts (b) use mains for a project (c) touch a switch when wet (d) stop if a part gets hot
5. 5.🧮 A 10 Ω resistor is joined in series with two equal 470 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
6. 6.🔁 count = 1
   while (count < 36) { count = count + 5 }
   How many times does the loop run?
7. 7.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) gets smaller (c) gets bigger (d) stays the same
8. 8.🔁 count = 1
   while (count < 17) { count = count + 4 }
   How many times does the loop run?
9. 9.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put aluminium foil across the gap. Does the bulb glow? (a) No (b) Yes
10. 10.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) pauses for half a second (c) blinks 500 times (d) turns the LED off
11. 11.🔋 How many 1.5 V cells must be joined in series to give 4.5 V?
12. 12.🤖 if (light < 300) { lamp ON } else { lamp OFF }
    The light sensor reads 260. What happens? (a) lamp ON (b) lamp OFF
13. 13.💡 An LED is joined to a 6 V battery with no resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) does not light (b) may burn out (c) lights up
14. 14.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
15. 15.🔗 Series or parallel circuit: “many paths for current”? (a) series (b) parallel
16. 16.🔌 Is aluminium foil a conductor or an insulator? (a) an insulator (b) a conductor
17. 17.📶 On a 5 V board, a pin set HIGH gives about … (a) 5 V (b) 0 V (c) 230 V (d) 50 V
18. 18.🏠 Which is a smart-home example? (a) a printed map (b) a candle in a jar (c) lights on from an app (d) a hand fan
19. 19.True or false: a plain rectangle is the symbol for a resistor. (a) True (b) False
20. 20.Which of these is true of a parallel circuit? (a) a single current path (b) used in house wiring (c) bulbs share the voltage (d) one bulb out, all go out
21. 21.🧮 Resistors of 10 Ω and 10 Ω are joined in series. What is the total resistance (in ohms)?
22. 22.Which of these mainly makes sound? (a) a torch (b) a ceiling fan (c) a school bell (d) a traffic signal
23. 23.🔺 A 3.75 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
24. 24.🗺️ In an input → process → output plan, is “check if temp > 30” the input, the process or the output? (a) process (b) output (c) input
25. 25.✏️ Why do engineers draw circuits with symbols? (a) quick and clear for all (b) to make it colourful (c) to hide the circuit (d) symbols are heavier
26. 26.🔍 Which is the odd one out? (a) stop if a part gets hot (b) use mains for a project (c) fly kites in open fields (d) build with an adult near
27. 27.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) dotted circles (c) wavy lines (d) straight lines
28. 28.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 HIGH
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
29. 29.🧮 Adding another resistor in series makes the total resistance … (a) stay the same (b) smaller (c) bigger (d) zero
30. 30.💡 An LED is joined to a 3 V battery through a 330 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) does not light (b) lights up (c) may burn out
31. 31.🔢 To run one loop of a plant-watering program, which comes first: “wait a few seconds” or “read the soil sensor”? (a) read the soil sensor (b) wait a few seconds
32. 32.🌐 A soil sensor sends a reading to an app every 15 minutes. How many readings arrive in 4 hours?
33. 33.🔌 Why are electric wires covered in plastic? (a) plastic is a conductor (b) plastic is an insulator (c) plastic makes current (d) to make them heavy
34. 34.✏️ In a circuit diagram, which part is drawn as a circle with a cross? (a) motor (b) bulb (c) resistor (d) wire
35. 35.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a plastic ruler. Does the bulb glow? (a) Yes (b) No
36. 36.⚡ What does a tube light mainly change electricity into? (a) light (b) heat (c) movement (d) sound
37. 37.🤖 “if (A AND B)” is true when … (a) only A is true (b) both are false (c) only B is true (d) both A and B are true
38. 38.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
39. 39.Which drawing is the symbol for a capacitor? (a) a circle with a cross (b) a dot where wires meet (c) triangle, bar and arrows (d) two equal parallel lines
40. 40.🗺️ In an input → process → output plan, is “a soil moisture reading” the input, the process or the output? (a) process (b) output (c) input

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