Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 974 · 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.🔌 Is an LED an input or an output for a microcontroller? (a) input (b) output
2. 2.True or false: “one bulb out, all go out” is true of a series circuit. (a) False (b) True
3. 3.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they keep glowing (b) they all go out (c) they get dimmer (d) they explode
4. 4.🧩 Which component has coloured bands? (a) potentiometer (b) LED (c) capacitor (d) resistor
5. 5.Which job is done by the USB port? (a) connect sensors and LEDs (b) shows the board is on (c) brings power and code (d) keeps the voltage steady
6. 6.✏️ In a circuit diagram, wires are usually drawn as … (a) straight lines (b) dotted circles (c) wavy lines (d) little stars
7. 7.🔺 A current of 10 mA flows through a 220 Ω resistor. What is the voltage across it (in volts)? =
8. 8.⚡ What does a traffic signal mainly change electricity into? (a) movement (b) sound (c) light (d) heat
9. 9.🔁 repeat 2 times { repeat 3 times { beep } }
   How many beeps are there?
10. 10.🤖 “if (A AND B)” is true when … (a) only A is true (b) both A and B are true (c) both are false (d) only B is true
11. 11.🤖 Does a plain wall switch usually have a microcontroller inside? (a) No (b) Yes
12. 12.Which of these has no microcontroller inside? (a) a TV remote (b) a washing machine (c) a wind-up toy (d) a toy robot
13. 13.True or false: “a light level reading” is the input. (a) True (b) False
14. 14.🔋 Cells joined + to − in a row (series) give … (a) the same voltage (b) no voltage (c) a smaller voltage (d) a bigger voltage
15. 15.🔢 To plan an electronics project, what comes right after “build it with an adult”? (a) pick a problem to solve (b) list inputs and outputs (c) draw the circuit diagram (d) test it and fix it
16. 16.🔺 A current of 0.1 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
17. 17.🔺 A current of 10 mA flows when 2.5 V is joined across a resistor. What is its resistance (in ohms)?
18. 18.🔺 A current of 0.25 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
19. 19.🔋 How many volts does one ordinary torch cell give? (a) 15 V (b) 230 V (c) 1.5 V (d) 0.5 V
20. 20.Which of these is an output? (a) a light sensor (b) a buzzer (c) a temperature sensor (d) a keypad
21. 21.🧮 Resistors of 22 Ω, 10 Ω and 330 Ω are joined in series. What is the total resistance (in ohms)?
22. 22.Which of these is an insulator? (a) a graphite rod (b) a glass marble (c) a metal paper clip (d) a copper wire
23. 23.Which of these is a good habit? (a) accept every permission (b) log out of shared phones (c) post your live location (d) share the Wi-Fi key
24. 24.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) stays the same (c) gets bigger (d) gets smaller
25. 25.True or false: “a single current path” is true of a series circuit. (a) False (b) True
26. 26.Which of these is a good habit? (a) tap unknown app links (b) change default passwords (c) keep factory passwords (d) accept every permission
27. 27.💡 A battery lights 5 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
28. 28.🔺 A 0.5 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
29. 29.🌈 A resistor has the colour bands white, yellow, black. What is its value (in ohms)?
30. 30.🔢 To run one loop of a plant-watering program, which is the FIRST step? (a) wait a few seconds (b) switch the pump on/off (c) compare with the limit (d) read the soil sensor
31. 31.🔁 count = 0
    repeat 2 times { count = count + 10 }
    What is count at the end?
32. 32.🔋 A 3 V battery and one 1.5 V cell are joined in series, all facing the same way. What is the total voltage (in volts)? =
33. 33.True or false: to spot someone walking in, use a light sensor. (a) True (b) False
34. 34.True or false: the ammeter is joined across a part. (a) False (b) True
35. 35.🗺️ In an input → process → output plan, is “a button press” the input, the process or the output? (a) output (b) process (c) input
36. 36.🔘 When a switch is ON, the circuit is … (a) open (b) broken (c) closed (d) cut
37. 37.💡 A red LED uses 2 V and should get 10 mA. It runs from a 9 V supply. What resistor (in ohms) is needed in series?
38. 38.⏱️ repeat 9 times { buzzer ON; wait 1000 ms; buzzer OFF; wait 900 ms }
    How many milliseconds does this take in all?
39. 39.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 630 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
40. 40.Which of these means the circuit is open? (a) all wires are joined (b) the loop is complete (c) the bulb is unscrewed (d) the switch is ON

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