Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 962 · 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.True or false: an LDR senses how bright it is. (a) False (b) True
2. 2.Which of these is a good habit? (a) post your live location (b) install software updates (c) reuse one password (d) share camera links
3. 3.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) tell it your passwords (b) let strangers use it (c) mute it when not in use (d) put it in the bathroom
4. 4.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
5. 5.📏 How many milliamperes (mA) is 2.37 A?
6. 6.🔢 To run one loop of a plant-watering program, what comes right after “read the soil sensor”? (a) compare with the limit (b) switch the pump on/off (c) wait a few seconds
7. 7.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) quick and clear for all (c) symbols are heavier (d) to hide the circuit
8. 8.True or false: on a cell, “the end with a bump” means the − (negative) end. (a) False (b) True
9. 9.🔺 A 2 V supply is joined across an 8 Ω resistor. What current flows (in amperes)? =
10. 10.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they get dimmer (b) they all go out (c) they explode (d) they keep glowing
11. 11.🧭 Which part of a microcontroller board runs the program? (a) the voltage regulator (b) the reset button (c) the USB port (d) the main chip
12. 12.True or false: a washing machine has no microcontroller inside. (a) True (b) False
13. 13.🔋 Does a television give electricity or use electricity? (a) uses electricity (b) gives electricity
14. 14.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
15. 15.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) False (b) True
16. 16.🔘 Which kind of switch closes near a magnet? (a) a tilt switch (b) a toggle switch (c) a push button (d) a reed switch
17. 17.🔍 Which is the odd one out? (a) a table fan (b) an LED lamp (c) a torch (d) a street light
18. 18.🔺 A current of 3 A flows when 12 V is joined across a resistor. What is its resistance (in ohms)?
19. 19.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) switch (b) cell (c) capacitor (d) motor
20. 20.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 8 LOW
    set pin 7 HIGH
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
21. 21.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
22. 22.🧮 Two equal 10 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
23. 23.🔺 A current of 2 A flows when 24 V is joined across a resistor. What is its resistance (in ohms)?
24. 24.🔋 4 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
25. 25.Which of these is safe? (a) poke things in a socket (b) use mains for a project (c) stay away from pylons (d) use a cable with cuts
26. 26.📶 How many states can a digital pin have? (a) a thousand (b) one (c) ten (d) two
27. 27.True or false: “many values in a range” is an analog signal. (a) False (b) True
28. 28.Which drawing is the symbol for a voltmeter? (a) a circle with an X in it (b) a circle with V inside (c) a line lifted at a gap (d) a dot where wires meet
29. 29.🌈 A resistor has the colour bands grey, brown, orange. What is its value in kilo-ohms (kΩ)? =
30. 30.🤖 if (light < 200) { lamp ON } else { lamp OFF }
    The light sensor reads 114. What happens? (a) lamp ON (b) lamp OFF
31. 31.🔁 count = 5
    while (count < 17) { count = count + 4 }
    How many times does the loop run?
32. 32.🔺 In the V-I-R triangle, how do we find I? (a) I = V × R (b) I = R ÷ V (c) I = V + R (d) I = V ÷ R
33. 33.🔍 Which is the odd one out? (a) an LED (b) a water pump (c) a keypad (d) a motor
34. 34.📶 Digital or analog: a button: pressed or not? (a) analog (b) digital
35. 35.🔍 Which is the odd one out? (a) climb an electric pole (b) fly kites in open fields (c) poke things in a socket (d) throw cells in a fire
36. 36.🔺 A current of 1.5 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
37. 37.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) diode (b) junction (c) bulb (d) capacitor
38. 38.🗺️ Before building a project, what should you write down first? (a) the final price (b) inputs and outputs (c) nothing at all (d) the box colour
39. 39.🔋 How many volts does one ordinary torch cell give? (a) 15 V (b) 0.5 V (c) 230 V (d) 1.5 V
40. 40.🌈 A gold fourth band on a resistor means the value may be off by … (a) 25 % (b) 50 % (c) 5 % (d) 0 %

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