Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 286 · 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.💡 In a series circuit, how many paths does the current have? (a) two (b) one (c) none (d) one for each bulb
2. 2.💡 2 identical bulbs are joined in series with a 4 V battery (ideal wires). How many volts does each bulb get? =
3. 3.True or false: on an LED, the leg by the flat edge is the cathode (−). (a) False (b) True
4. 4.🔦 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 copper wire. Does the bulb glow? (a) Yes (b) No
5. 5.🔁 total = 0
   for i = 1 to 7 { total = total + i }
   What is total at the end?
6. 6.🧮 Resistors of 50 Ω, 68 Ω, 50 Ω and 33 Ω are joined in series. What is the total resistance (in ohms)?
7. 7.🗺️ In an input → process → output plan, is “check if temp > 30” the input, the process or the output? (a) input (b) output (c) process
8. 8.True or false: a loudspeaker mainly makes movement. (a) False (b) True
9. 9.🔌 Is a plastic ruler a conductor or an insulator? (a) a conductor (b) an insulator
10. 10.🤖 if (temperature > 33) { show “Hot” } else if (temperature > 18) { show “Warm” } else { show “Cool” }
    The temperature is 18 °C. What is shown? (a) Cool (b) Warm (c) Hot
11. 11.⏱️ A program says “wait 6500 ms”. How many seconds is that? =
12. 12.⏱️ loop forever { LED ON; wait 250 ms; LED OFF; wait 150 ms }
    How many times does the LED blink in 10 seconds?
13. 13.🧮 Resistors of 220 Ω and 220 Ω are joined in series. What is the total resistance (in ohms)?
14. 14.True or false: if the bulb is unscrewed, the circuit is open and no current flows. (a) True (b) False
15. 15.True or false: to share the Wi-Fi key is a risky habit. (a) True (b) False
16. 16.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) the shorter line (c) neither line (d) both lines
17. 17.🌐 A weather station sends one reading every 30 seconds. How many readings does it send in 4 minutes?
18. 18.True or false: “the fan starts” is the input. (a) True (b) False
19. 19.🔢 To plan an electronics project, what comes right after “pick a problem to solve”? (a) test it and fix it (b) build it with an adult (c) list inputs and outputs (d) draw the circuit diagram
20. 20.🔍 Which sensor would you use to keep an incubator warm? (a) a sound sensor (b) a rain sensor (c) a temperature sensor (d) a distance sensor
21. 21.True or false: a thermistor turns a fan or wheels. (a) False (b) True
22. 22.🧮 A 1.2 V battery is joined to 4 Ω and 2 Ω resistors in series. What current flows (in amperes)? =
23. 23.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 920 Ω resistor? (a) white-red-black (b) red-white-brown (c) white-red-red (d) white-red-brown
24. 24.🔺 A current of 0.1 A flows through a 15 Ω resistor. What is the voltage across it (in volts)? =
25. 25.⚠️ Which power source should children use for electronics projects? (a) a small battery pack (b) a mains extension board (c) a wall socket (d) an inverter socket
26. 26.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 2 hours. How many watt-hours (Wh) are saved?
27. 27.🔁 count = 10
    repeat 8 times { count = count + 9 }
    What is count at the end?
28. 28.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) gets bigger (c) stays the same (d) gets smaller
29. 29.True or false: a thermistor beeps for an alarm. (a) True (b) False
30. 30.🔍 Which is the odd one out? (a) a motion sensor signal (b) a soil moisture reading (c) a light level reading (d) compare with a limit
31. 31.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a copper wire across the gap. Does the bulb glow? (a) Yes (b) No
32. 32.Which of these is the output? (a) check if temp > 30 (b) compare with a limit (c) the fan starts (d) a soil moisture reading
33. 33.⏱️ How many milliseconds is a wait of 2.4 seconds?
34. 34.📶 Digital or analog: how bright a room is? (a) analog (b) digital
35. 35.True or false: “a motion sensor signal” is the process. (a) False (b) True
36. 36.True or false: “used in house wiring” is true of a parallel circuit. (a) True (b) False
37. 37.Which of these is true of a series circuit? (a) own switch for each bulb (b) many paths for current (c) each gets the full volts (d) a break stops every bulb
38. 38.⚙️ Which actuator would you use to spin a robot’s wheels? (a) a buzzer (b) a pump (c) an LED (d) a motor
39. 39.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) + (positive) (b) − (negative)
40. 40.🧭 Which part of a microcontroller board restarts the program? (a) the main chip (b) the voltage regulator (c) the reset button (d) the pins

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