Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 299 · 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.🌈 A resistor has the colour bands red, red, red. What is its value (in ohms)?
2. 2.What does a resistor do? (a) senses how hot it is (b) has coloured bands (c) lets current go one way (d) makes a beeping sound
3. 3.🧩 A capacitor in a circuit can … (a) make light (b) store charge briefly (c) spin a wheel (d) measure heat
4. 4.🌐 In an IoT system, which part carries the data? (a) phone app (b) cloud server (c) actuator (d) Wi-Fi
5. 5.True or false: to dry your hands first is not safe. (a) False (b) True
6. 6.True or false: “one bulb out, all go out” is true of a series circuit. (a) True (b) False
7. 7.Which of these is the output? (a) count button presses (b) check if temp > 30 (c) a buzzer beeps (d) a button press
8. 8.🧾 A 1500 W appliance runs for 10 hours. How many units (kWh) of electricity does it use? =
9. 9.True or false: a glass marble is a conductor. (a) True (b) False
10. 10.🌐 What does IoT stand for? (a) Internet of Things (b) Inside of Toys (c) Input of Tools (d) Internet of Talk
11. 11.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) ask a parent first (b) share it with friends (c) type it all in (d) post it online
12. 12.🧩 Which component smooths a wobbly supply? (a) fuse (b) resistor (c) capacitor (d) thermistor
13. 13.Which of these is an input? (a) a temperature sensor (b) an LED (c) a small display (d) a servo motor
14. 14.True or false: “one out, the rest glow” is true of a series circuit. (a) True (b) False
15. 15.🌐 Is a wind-up clock an IoT device? (a) an IoT device (b) not an IoT device
16. 16.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) series (b) parallel
17. 17.🔁 What must there be for a current to flow? (a) a plastic gap (b) one loose end (c) a complete loop (d) a broken path
18. 18.True or false: “a break stops every bulb” is true of a series circuit. (a) False (b) True
19. 19.💡 A battery lights 2 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
20. 20.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 350 ms }
    How many times does the LED blink in 2 seconds?
21. 21.💡 An LED is joined to a 6 V battery through a 330 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) lights up (b) does not light (c) may burn out
22. 22.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) + (positive) (b) − (negative)
23. 23.🧾 A 250 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
24. 24.🤖 if (moisture < 50) { pump ON } else { pump OFF }
    The soil moisture sensor reads 33 %. What happens? (a) pump OFF (b) pump ON
25. 25.🔁 repeat 4 times { repeat 4 times { beep } }
    How many beeps are there?
26. 26.💡 A battery lights 5 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
27. 27.True or false: if all wires are joined, the circuit is open and no current flows. (a) True (b) False
28. 28.What does a reed switch do? (a) closes when tipped over (b) works only while pressed (c) flips up or down (d) closes near a magnet
29. 29.⚠️ Which power source should children use for electronics projects? (a) a mains extension board (b) a small battery pack (c) an inverter socket (d) a wall socket
30. 30.💡 A battery lights 4 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same
31. 31.🌈 A resistor has the colour bands grey, grey, yellow. What is its value in kilo-ohms (kΩ)? =
32. 32.🔍 Which is the odd one out? (a) stop if a part gets hot (b) throw cells in a fire (c) dry your hands first (d) keep drinks far away
33. 33.🔍 Which is the odd one out? (a) iron one shirt at a time (b) use daylight to read (c) use old filament bulbs (d) leave fridge door open
34. 34.⏱️ How many milliseconds is a wait of 0.3 seconds?
35. 35.What does a toggle switch do? (a) slides side to side (b) works only while pressed (c) closes when tipped over (d) flips up or down
36. 36.Which drawing is the symbol for a junction? (a) many long-short pairs (b) two or more cell symbols (c) a circle with an X in it (d) a dot where wires meet
37. 37.What does a diode do? (a) boosts a small signal (b) lets current go one way (c) makes things spin (d) smooths a wobbly supply
38. 38.🌐 A soil sensor sends a reading to an app every 20 minutes. How many readings arrive in 1 hour?
39. 39.Which drawing is the symbol for an LED? (a) triangle, bar and arrows (b) a long and a short line (c) many long-short pairs (d) a dot where wires meet
40. 40.🔺 A 0.2 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =

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