Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 558 · 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.🔢 To plan an electronics project, which comes first: “draw the circuit diagram” or “build it with an adult”? (a) build it with an adult (b) draw the circuit diagram
2. 2.🌐 In an IoT system, which part shows data to you? (a) microcontroller (b) Wi-Fi (c) sensor (d) phone app
3. 3.🔍 Which is the odd one out? (a) a servo motor (b) a speaker (c) a keypad (d) an LED
4. 4.True or false: on an LED, the shorter leg is the anode (+). (a) True (b) False
5. 5.🔺 A 3.75 V supply is joined across a 150 Ω resistor. What current flows (in milliamperes, mA)?
6. 6.What does the phone app do? (a) shows data to you (b) measures the real world (c) acts on a command (d) reads values, decides
7. 7.True or false: a slide switch slides side to side. (a) False (b) True
8. 8.🔁 What does a variable do in a program? (a) measures light (b) blinks an LED (c) joins two wires (d) stores a value
9. 9.🔍 Which is the odd one out? (a) a buzzer beeps (b) an alert on the phone (c) the pump turns on (d) a soil moisture reading
10. 10.🔌 Why are electric wires covered in plastic? (a) to make them heavy (b) plastic makes current (c) plastic is an insulator (d) plastic is a conductor
11. 11.Which of these is a good habit? (a) keep factory passwords (b) reuse one password (c) post your live location (d) read app permissions
12. 12.💡 3 identical bulbs are joined in series with a 3 V battery (ideal wires). How many volts does each bulb get? =
13. 13.🔋 How many volts does one ordinary torch cell give? (a) 0.5 V (b) 15 V (c) 1.5 V (d) 230 V
14. 14.💡 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) may burn out (b) does not light (c) lights up
15. 15.🔍 Which sensor would you use to water a dry plant? (a) a rain sensor (b) a soil moisture sensor (c) a sound sensor (d) a distance sensor
16. 16.Which of these is measured in watts (W)? (a) resistance (b) how much a part resists (c) voltage (d) power
17. 17.🔦 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 cotton thread. Does the bulb glow? (a) No (b) Yes
18. 18.True or false: a hand pump has no microcontroller inside. (a) True (b) False
19. 19.🔁 x = 2
    repeat 3 times { x = x × 2 }
    What is x at the end?
20. 20.⏱️ How many milliseconds is a wait of 0.9 seconds?
21. 21.🧮 A 68 Ω resistor is joined in series with two equal 330 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
22. 22.True or false: a hand pump usually has a microcontroller inside. (a) True (b) False
23. 23.💡 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
24. 24.🧩 Which component senses how bright it is? (a) potentiometer (b) LDR (c) thermistor (d) diode
25. 25.🔺 A current of 0.1 A flows through a 12 Ω resistor. What is the voltage across it (in volts)? =
26. 26.True or false: if the loop is complete, the circuit is closed and current flows. (a) True (b) False
27. 27.🔁 Is the circuit closed or open if all wires are joined? (a) open (b) closed
28. 28.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the USB port (b) the reset button (c) the voltage regulator (d) the pins
29. 29.True or false: a capacitor boosts a small signal. (a) True (b) False
30. 30.🧩 Which part changes electrical energy into sound? (a) a resistor (b) a buzzer (c) a diode (d) a capacitor
31. 31.🔘 Which kind of switch slides side to side? (a) a tilt switch (b) a reed switch (c) a toggle switch (d) a slide switch
32. 32.💡 What happens if an LED is put in backwards? (a) it does not light (b) it makes a sound (c) it changes colour (d) it lights brighter
33. 33.🌐 A weather station sends one reading every 60 seconds. How many readings does it send in 2 minutes?
34. 34.Which of these is measured in ohms (Ω)? (a) the push of a cell (b) the flow of charge (c) power (d) resistance
35. 35.🔁 repeat 4 times { repeat 5 times { beep } }
    How many beeps are there?
36. 36.🔁 count = 3
    repeat 7 times { count = count + 6 }
    What is count at the end?
37. 37.🔍 Which sensor would you use to keep an incubator warm? (a) a sound sensor (b) a temperature sensor (c) a rain sensor (d) a light sensor
38. 38.🔦 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
39. 39.🤖 Microcontroller or laptop: which one runs many apps at once? (a) microcontroller (b) laptop
40. 40.Which of these is the input? (a) check if temp > 30 (b) a soil moisture reading (c) the pump turns on (d) count button presses

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