Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 800 · 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 2.4 V supply is joined across a 12 Ω resistor. What current flows (in amperes)? =
2. 2.🔌 Is a water pump an input or an output for a microcontroller? (a) input (b) output
3. 3.True or false: to fly kites in open fields is safe. (a) False (b) True
4. 4.✏️ In a cell symbol, which line is the + terminal? (a) the shorter line (b) both lines (c) the longer line (d) neither line
5. 5.Which of these is not safe? (a) keep drinks far away (b) use small battery cells (c) fly kites in open fields (d) climb an electric pole
6. 6.🌐 In an IoT system, which part shows data to you? (a) sensor (b) actuator (c) Wi-Fi (d) phone app
7. 7.🔘 Which kind of switch closes near a magnet? (a) a slide switch (b) a reed switch (c) a toggle switch (d) a tilt switch
8. 8.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) True (b) False
9. 9.True or false: to keep an incubator warm, use a sound sensor. (a) True (b) False
10. 10.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) type it all in (b) ask a parent first (c) share it with friends (d) post it online
11. 11.True or false: one tall, one short bar is the symbol for an LED. (a) True (b) False
12. 12.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 7 LOW
    set pin 7 HIGH
    set pin 8 HIGH
    set pin 7 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
13. 13.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
14. 14.🧭 Which part of a microcontroller board keeps the voltage steady? (a) the voltage regulator (b) the USB port (c) the reset button (d) the pins
15. 15.⚠️ Is it safe to climb an electric pole? (a) safe (b) not safe
16. 16.True or false: a slide switch stays where you flip it. (a) True (b) False
17. 17.Which of these is a good habit? (a) share camera links (b) share the Wi-Fi key (c) log out of shared phones (d) tap unknown app links
18. 18.⚡ Which formula gives electric power? (a) P = V + I (b) P = V × I (c) P = I ÷ V (d) P = V ÷ I
19. 19.Which of these mainly gives out light? (a) a siren (b) a doorbell (c) a night lamp (d) a school bell
20. 20.🧾 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?
21. 21.🌈 A resistor has the colour bands blue, brown, red. What is its value in kilo-ohms (kΩ)? =
22. 22.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) a cell is taken out (c) all wires are joined (d) the switch is OFF
23. 23.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 280 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
24. 24.🔋 Does a computer give electricity or use electricity? (a) gives electricity (b) uses electricity
25. 25.⚡ A bicycle dynamo changes which kind of energy into electricity? (a) sound energy (b) chemical energy (c) movement energy (d) light energy
26. 26.⚠️ A cell gets hot when its + and − ends are joined by a bare wire. What is this called? (a) a safe circuit (b) an open circuit (c) a short circuit (d) a parallel circuit
27. 27.🔍 Which is the odd one out? (a) an LED (b) a motor (c) a light sensor (d) a water pump
28. 28.True or false: a buzzer mainly makes sound. (a) True (b) False
29. 29.🧾 A 2000 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
30. 30.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) none (c) two (d) one
31. 31.True or false: on a cell, “the end with a bump” means the − (negative) end. (a) False (b) True
32. 32.💡 Does it save or waste electricity to leave fridge door open? (a) wastes electricity (b) saves electricity
33. 33.🧭 Which part of a microcontroller board shows the board is on? (a) the voltage regulator (b) the power LED (c) the reset button (d) the USB port
34. 34.🌐 In an IoT system, which part stores data online? (a) actuator (b) cloud server (c) microcontroller (d) Wi-Fi
35. 35.🤖 Does a bicycle bell usually have a microcontroller inside? (a) No (b) Yes
36. 36.Which of these is measured in amperes (A)? (a) the push of a cell (b) energy used each second (c) current (d) power
37. 37.🔘 Two switches are in series. When does the bulb glow? (a) when either is ON (b) when both are ON (c) never (d) when both are OFF
38. 38.✏️ In a circuit diagram, wires are usually drawn as … (a) straight lines (b) little stars (c) wavy lines (d) dotted circles
39. 39.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) switch off empty rooms (c) leave the TV on standby (d) unplug idle chargers
40. 40.Which of these is a good habit? (a) cover unused cameras (b) reuse one password (c) share the Wi-Fi key (d) accept every permission

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