Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 115 · 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.🔍 Which is the odd one out? (a) a plastic straw (b) a steel spoon (c) a brass key (d) a metal paper clip
2. 2.🧮 Four equal 100 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
3. 3.💡 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
4. 4.🧾 A 75 W filament bulb is swapped for a 12 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
5. 5.Which of these is the input? (a) check if temp > 30 (b) an alert on the phone (c) count button presses (d) a soil moisture reading
6. 6.True or false: to iron one shirt at a time wastes electricity. (a) True (b) False
7. 7.True or false: to use daylight to read saves electricity. (a) False (b) True
8. 8.Which of these usually has a microcontroller inside? (a) a wind-up toy (b) a candle (c) a bicycle bell (d) a digital alarm clock
9. 9.True or false: a table fan mainly gives out light. (a) True (b) False
10. 10.Which of these is a risky habit? (a) log out of shared phones (b) change default passwords (c) cover unused cameras (d) post your live location
11. 11.🔌 Which part of a screwdriver should an electrician hold? (a) the plastic handle (b) the metal tip (c) the steel shaft (d) the bare end
12. 12.Which of these has no microcontroller inside? (a) a digital alarm clock (b) a candle (c) a TV remote (d) a toy robot
13. 13.🔌 Is a rubber band a conductor or an insulator? (a) an insulator (b) a conductor
14. 14.🔢 To get a sensor reading onto a phone, what comes right after “the sensor measures”? (a) the cloud stores it (b) the board reads it (c) it is sent by Wi-Fi (d) the app shows it
15. 15.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 7 LOW
    set pin 7 HIGH
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
16. 16.🔍 Which is the odd one out? (a) a ceramic cup (b) a copper wire (c) a metal paper clip (d) a brass key
17. 17.🧩 A capacitor in a circuit can … (a) store charge briefly (b) measure heat (c) spin a wheel (d) make light
18. 18.Which of these is a conductor? (a) a paper strip (b) a plastic straw (c) aluminium foil (d) a cotton thread
19. 19.🔌 Is a sound sensor an input or an output for a microcontroller? (a) output (b) input
20. 20.🧩 Which component stores a little charge? (a) LED (b) resistor (c) LDR (d) capacitor
21. 21.🧮 Two equal 200 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
22. 22.🔌 Is a motor an input or an output for a microcontroller? (a) output (b) input
23. 23.🔍 Which is the odd one out? (a) set up with a parent (b) change default passwords (c) share the Wi-Fi key (d) install software updates
24. 24.🔁 x = 5
    repeat 3 times { x = x × 2 }
    What is x at the end?
25. 25.⚡ What does an electric drill mainly change electricity into? (a) light (b) movement (c) sound (d) heat
26. 26.⚠️ Who should be with you when you build a circuit? (a) a stranger online (b) a younger child (c) nobody (d) a trusted adult
27. 27.True or false: a steel spoon is an insulator. (a) True (b) False
28. 28.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) when either is ON (b) only when both are ON (c) never (d) only when both are OFF
29. 29.🔋 Does a bicycle dynamo give electricity or use electricity? (a) gives electricity (b) uses electricity
30. 30.Which of these mainly makes sound? (a) a night lamp (b) an electric drill (c) a rice cooker (d) a siren
31. 31.⏱️ loop forever { LED ON; wait 1600 ms; LED OFF; wait 400 ms }
    How many times does the LED blink in 8 seconds?
32. 32.📶 Digital or analog: a tilt switch: on or off? (a) digital (b) analog
33. 33.🗺️ In an input → process → output plan, is “check if temp > 30” the input, the process or the output? (a) output (b) input (c) process
34. 34.🔺 A current of 25 mA flows when 2.5 V is joined across a resistor. What is its resistance (in ohms)?
35. 35.🌐 How does a home IoT device usually send its data to the app? (a) by shouting (b) through a candle (c) by post (d) over Wi-Fi
36. 36.⚡ Power tells us … (a) the colour of light (b) energy used each second (c) the size of a cell (d) the length of a wire
37. 37.True or false: a thermistor senses how hot it is. (a) False (b) True
38. 38.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets smaller (b) becomes zero (c) gets bigger (d) stays the same
39. 39.True or false: “many values in a range” is an analog signal. (a) False (b) True
40. 40.🔺 In the V-I-R triangle, how do we find I? (a) I = V + R (b) I = V × R (c) I = V ÷ R (d) I = R ÷ V

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