Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 93 · 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 of these is a conductor? (a) a cotton thread (b) a metal paper clip (c) a rubber eraser (d) a woollen thread
2. 2.🔁 total = 0
   for i = 1 to 11 { total = total + i }
   What is total at the end?
3. 3.⚡ A 3 W device works on 6 V. What current does it take (in amperes)? =
4. 4.🧩 Which component stores a little charge? (a) buzzer (b) transistor (c) capacitor (d) potentiometer
5. 5.🔋 7 identical 3 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
6. 6.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) + (positive) (b) − (negative)
7. 7.🔍 Which is the odd one out? (a) a light level reading (b) a soil moisture reading (c) decide if soil is dry (d) a button press
8. 8.🔍 Which is the odd one out? (a) an LED (b) a keypad (c) a buzzer (d) a motor
9. 9.🧮 Four equal 80 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
10. 10.Which of these wastes electricity? (a) use daylight to read (b) set the AC to 24 °C (c) leave fridge door open (d) switch off empty rooms
11. 11.⚡ A home appliance on the 230 V mains takes 2 A. What is its power (in watts)?
12. 12.True or false: a straight line is the symbol for a motor. (a) True (b) False
13. 13.🔍 Which is the odd one out? (a) leave fridge door open (b) unplug idle chargers (c) leave the TV on standby (d) use old filament bulbs
14. 14.🔍 Which is the odd one out? (a) a torch (b) a toaster (c) an LED lamp (d) a street light
15. 15.What does an LDR do? (a) senses how bright it is (b) smooths a wobbly supply (c) turns a fan or wheels (d) makes things spin
16. 16.🔁 count = 1
    repeat 8 times { count = count + 9 }
    What is count at the end?
17. 17.📏 Voltmeter or ammeter: which one is joined across a part? (a) ammeter (b) voltmeter
18. 18.🔍 Which is the odd one out? (a) share camera links (b) ignore update messages (c) share only needed data (d) tap unknown app links
19. 19.🔐 Privacy for a smart device means controlling … (a) how loud it beeps (b) who can see your data (c) its colour (d) its battery size
20. 20.True or false: “own switch for each bulb” is true of a series circuit. (a) True (b) False
21. 21.⏱️ loop forever { LED ON; wait 700 ms; LED OFF; wait 300 ms }
    How many milliseconds does one blink (ON + OFF) take?
22. 22.🌈 A resistor has the colour bands yellow, blue, brown. What is its value (in ohms)?
23. 23.🔺 A current of 25 mA flows when 5.5 V is joined across a resistor. What is its resistance (in ohms)?
24. 24.⚠️ A cell gets hot when its + and − ends are joined by a bare wire. What is this called? (a) a safe circuit (b) a parallel circuit (c) an open circuit (d) a short circuit
25. 25.🧩 Which part changes electrical energy into sound? (a) a diode (b) a resistor (c) a capacitor (d) a buzzer
26. 26.🌈 A resistor has the colour bands brown, brown, red. What is its value (in ohms)?
27. 27.True or false: “one bulb out, all go out” is true of a series circuit. (a) True (b) False
28. 28.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a fuse (c) an input (d) a power source
29. 29.🤖 Microcontroller or laptop: which one has no screen of its own? (a) microcontroller (b) laptop
30. 30.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) bigger (c) stay the same (d) smaller
31. 31.🧮 Five equal 500 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
32. 32.🔁 What must there be for a current to flow? (a) a broken path (b) a complete loop (c) one loose end (d) a plastic gap
33. 33.⏱️ loop forever { LED ON; wait 250 ms; LED OFF; wait 250 ms }
    How many times does the LED blink in 7 seconds?
34. 34.True or false: a water heater mainly makes sound. (a) False (b) True
35. 35.📏 Voltmeter or ammeter: which one measures voltage? (a) ammeter (b) voltmeter
36. 36.🧮 A 6 V battery is joined to 4 Ω and 8 Ω resistors in series. What current flows (in amperes)? =
37. 37.Which job is done by the pins? (a) brings power and code (b) runs the program (c) connect sensors and LEDs (d) restarts the program
38. 38.✏️ In a cell symbol, which line is the + terminal? (a) the shorter line (b) neither line (c) the longer line (d) both lines
39. 39.🔗 Series or parallel circuit: “a single current path”? (a) series (b) parallel
40. 40.📏 How many amperes (A) is 1150 mA? =

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