Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 580 · 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: a tilt switch stays where you flip it. (a) False (b) True
2. 2.🌐 Is a fitness band with app an IoT device? (a) an IoT device (b) not an IoT device
3. 3.🧩 Which component glows using little power? (a) capacitor (b) LED (c) buzzer (d) diode
4. 4.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they get dimmer (b) they keep glowing (c) they explode (d) they all go out
5. 5.💡 What happens if an LED is put in backwards? (a) it lights brighter (b) it changes colour (c) it makes a sound (d) it does not light
6. 6.🗺️ In an input → process → output plan, is “compare with a limit” the input, the process or the output? (a) input (b) process (c) output
7. 7.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 3 hours. How many watt-hours (Wh) are saved?
8. 8.⚠️ Is it safe to fly kites in open fields? (a) not safe (b) safe
9. 9.💡 A red LED (it uses 2 V) is joined with a 200 Ω resistor to a 5 V supply. What current flows (in mA)?
10. 10.⏱️ How many milliseconds are in 1 second? (a) 60 (b) 1000 (c) 10 (d) 100
11. 11.Which of these mainly makes sound? (a) a doorbell (b) a table fan (c) a toaster (d) a night lamp
12. 12.🔁 x = 2
    repeat 1 time { x = x × 2 }
    What is x at the end?
13. 13.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 7 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
14. 14.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) False (b) True
15. 15.True or false: “each gets the full volts” is true of a series circuit. (a) False (b) True
16. 16.🌈 A resistor has the colour bands blue, brown, orange. What is its value in kilo-ohms (kΩ)? =
17. 17.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
18. 18.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
19. 19.🔁 count = 3
    while (count < 28) { count = count + 5 }
    How many times does the loop run?
20. 20.True or false: “many paths for current” is true of a series circuit. (a) False (b) True
21. 21.True or false: on an LED, the longer leg is the cathode (−). (a) False (b) True
22. 22.🔗 Series or parallel circuit: “many paths for current”? (a) parallel (b) series
23. 23.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 volt (c) 1 watt (d) 1 kilowatt-hour (kWh)
24. 24.🔺 A current of 10 mA flows when 1.5 V is joined across a resistor. What is its resistance (in ohms)?
25. 25.💡 A battery lights 3 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same
26. 26.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) the if part (c) the else part (d) neither part
27. 27.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in series (b) not joined (c) in parallel (d) by Wi-Fi
28. 28.🧩 A capacitor in a circuit can … (a) measure heat (b) make light (c) store charge briefly (d) spin a wheel
29. 29.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) none (c) one (d) two
30. 30.True or false: to share the Wi-Fi key is a risky habit. (a) True (b) False
31. 31.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 56000 Ω resistor? (a) green-blue-orange (b) green-blue-red (c) green-blue-yellow (d) blue-green-orange
32. 32.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is OFF, B is OFF and C is OFF. Does the bulb glow? (a) No (b) Yes
33. 33.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 9 hours. How many watt-hours (Wh) are saved?
34. 34.True or false: a dot where wires meet is the symbol for a junction. (a) False (b) True
35. 35.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) stays the same (b) gets smaller (c) gets bigger (d) becomes zero
36. 36.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
37. 37.What does a buzzer do? (a) boosts a small signal (b) makes a beeping sound (c) is a resistance knob (d) senses how bright it is
38. 38.🤖 if (temperature > 38) { show “Hot” } else if (temperature > 18) { show “Warm” } else { show “Cool” }
    The temperature is 24 °C. What is shown? (a) Warm (b) Cool (c) Hot
39. 39.🔺 In the V-I-R triangle, how do we find V? (a) V = R ÷ I (b) V = I + R (c) V = I × R (d) V = I ÷ R
40. 40.🔍 Which is the odd one out? (a) dry your hands first (b) poke things in a socket (c) use small battery cells (d) keep drinks far away

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