Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 324 · 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 “input → process → output”, which part is the decision the program makes? (a) the output (b) the battery (c) the process (d) the input
2. 2.🧮 Two resistors in parallel give a total that is … (a) less than either one (b) more than either one (c) always zero (d) their sum
3. 3.Which job needs a light sensor? (a) make a parking alarm (b) switch on lamps at dusk (c) close a window in rain (d) keep an incubator warm
4. 4.🔗 Series or parallel circuit: “one out, the rest glow”? (a) series (b) parallel
5. 5.🧭 Which part of a microcontroller board runs the program? (a) the main chip (b) the pins (c) the reset button (d) the USB port
6. 6.Which of these means the circuit is open? (a) the bulb is unscrewed (b) all wires are joined (c) the loop is complete (d) the switch is ON
7. 7.🔺 A current of 2 A flows when 4 V is joined across a resistor. What is its resistance (in ohms)?
8. 8.📶 A pin that reads a push button is set as … (a) a battery (b) an input (c) an output (d) a resistor
9. 9.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) a candle (c) an oil lamp (d) an LED lamp
10. 10.🔺 A 9 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
11. 11.🔺 A current of 1 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
12. 12.🌈 A gold fourth band on a resistor means the value may be off by … (a) 25 % (b) 5 % (c) 0 % (d) 50 %
13. 13.💡 In a series circuit, how many paths does the current have? (a) one for each bulb (b) one (c) none (d) two
14. 14.🧩 Which part changes electrical energy into sound? (a) a capacitor (b) a diode (c) a buzzer (d) a resistor
15. 15.🔍 An object is 68 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
16. 16.Which of these is not safe? (a) use small battery cells (b) dry your hands first (c) build with an adult near (d) open a phone charger
17. 17.🌐 Is a fitness band with app an IoT device? (a) not an IoT device (b) an IoT device
18. 18.True or false: to leave fridge door open saves electricity. (a) True (b) False
19. 19.Which of these is a conductor? (a) a graphite rod (b) a cotton thread (c) a glass marble (d) a woollen thread
20. 20.⚙️ Which actuator would you use to move water to plants? (a) a buzzer (b) a motor (c) a servo motor (d) a pump
21. 21.🔍 Which is the odd one out? (a) a brass key (b) a wooden stick (c) a cotton thread (d) a rubber band
22. 22.🔐 Is it a good or a risky habit to set up with a parent? (a) risky habit (b) good habit
23. 23.⚡ Which formula gives electric power? (a) P = I ÷ V (b) P = V ÷ I (c) P = V × I (d) P = V + I
24. 24.True or false: to use a cable with cuts is not safe. (a) True (b) False
25. 25.🔐 Is it a good or a risky habit to cover unused cameras? (a) good habit (b) risky habit
26. 26.Which of these is the process? (a) a soil moisture reading (b) a motion sensor signal (c) check if temp > 30 (d) an LED lights up
27. 27.✏️ In a circuit diagram, wires are usually drawn as … (a) straight lines (b) dotted circles (c) wavy lines (d) little stars
28. 28.Which of these saves electricity? (a) use old filament bulbs (b) close the fridge quickly (c) run fans in empty rooms (d) leave the TV on standby
29. 29.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) by Wi-Fi (b) in series (c) not joined (d) in parallel
30. 30.🔺 A current of 40 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
31. 31.Which of these has no microcontroller inside? (a) a digital alarm clock (b) a digital thermometer (c) a toy robot (d) a wind-up toy
32. 32.🔍 Which is the odd one out? (a) a light level reading (b) a soil moisture reading (c) a button press (d) check if temp > 30
33. 33.Which of these has no microcontroller inside? (a) a toy robot (b) a plain wall switch (c) a digital thermometer (d) a smart watch
34. 34.⚙️ What is an actuator? (a) a battery (b) an output that acts (c) a sensor (d) a program
35. 35.True or false: “a door: open or shut” is a digital signal. (a) False (b) True
36. 36.🔁 repeat 4 times { repeat 4 times { beep } }
    How many beeps are there?
37. 37.🔘 Which kind of switch springs back when let go? (a) a slide switch (b) a reed switch (c) a push button (d) a toggle switch
38. 38.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 7 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
39. 39.True or false: an LDR blows if current is high. (a) True (b) False
40. 40.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 1000 (c) 60 (d) 100

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