Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 559 · 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 job is done by the voltage regulator? (a) connect sensors and LEDs (b) shows the board is on (c) restarts the program (d) keeps the voltage steady
2. 2.🔘 Two switches are in series. When does the bulb glow? (a) when both are ON (b) never (c) when either is ON (d) when both are OFF
3. 3.📶 Digital or analog: how bright a room is? (a) digital (b) analog
4. 4.🧮 A 3.5 V battery is joined to 2 Ω and 5 Ω resistors in series. What current flows (in amperes)? =
5. 5.🤖 if (distance < 20) { buzzer beeps } else { buzzer is silent }
   The distance sensor reads 23 cm. What happens? (a) buzzer is silent (b) buzzer beeps
6. 6.🔋 6 identical 2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
7. 7.🔢 To plan an electronics project, which comes first: “pick a problem to solve” or “test it and fix it”? (a) pick a problem to solve (b) test it and fix it
8. 8.Which drawing is the symbol for a motor? (a) two or more cell symbols (b) triangle, bar and arrows (c) a circle with M inside (d) a plain rectangle
9. 9.✏️ In a cell symbol, which line is the + terminal? (a) neither line (b) the longer line (c) the shorter line (d) both lines
10. 10.💡 A blue LED uses 3 V and should get 25 mA. It runs from a 12 V supply. What resistor (in ohms) is needed in series?
11. 11.🔍 Which is the odd one out? (a) a torch (b) an LED lamp (c) a night lamp (d) a siren
12. 12.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
13. 13.Which of these mainly makes movement? (a) a buzzer (b) a ceiling fan (c) an LED lamp (d) an electric iron
14. 14.True or false: “how loud a sound is” is an analog signal. (a) True (b) False
15. 15.⚡ A 15 W device works on 5 V. What current does it take (in amperes)? =
16. 16.⚡ A bicycle dynamo changes which kind of energy into electricity? (a) chemical energy (b) sound energy (c) light energy (d) movement energy
17. 17.🔍 Which is the odd one out? (a) an app-controlled bulb (b) a pencil sharpener (c) a smart energy meter (d) a Wi-Fi smart plug
18. 18.🤖 if (distance < 10) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 15 cm. What happens? (a) buzzer beeps (b) buzzer is silent
19. 19.🔺 In the V-I-R triangle, how do we find V? (a) V = R ÷ I (b) V = I ÷ R (c) V = I + R (d) V = I × R
20. 20.⚡ What does a table fan mainly change electricity into? (a) movement (b) heat (c) sound (d) light
21. 21.🤖 What is a microcontroller? (a) a type of battery (b) a kind of bulb (c) a big desktop computer (d) a computer on one chip
22. 22.🔗 Series or parallel circuit: “one out, the rest glow”? (a) parallel (b) series
23. 23.🔺 A 1.6 V supply is joined across an 8 Ω resistor. What current flows (in amperes)? =
24. 24.🗺️ In an input → process → output plan, is “check if temp > 30” the input, the process or the output? (a) input (b) process (c) output
25. 25.🔍 Which is the odd one out? (a) a motion sensor signal (b) a soil moisture reading (c) check if temp > 30 (d) a button press
26. 26.💡 Why does an LED need a resistor in series? (a) to make it brighter (b) to store charge (c) to change its colour (d) to limit the current
27. 27.Which of these uses electricity? (a) a computer (b) a power station (c) a bicycle dynamo (d) a wind turbine
28. 28.True or false: to ignore update messages is a good habit. (a) True (b) False
29. 29.🔘 Which kind of switch flips up or down? (a) a push button (b) a slide switch (c) a tilt switch (d) a toggle switch
30. 30.📏 Voltmeter or ammeter: which one is joined in series? (a) voltmeter (b) ammeter
31. 31.True or false: a microcontroller uses very little power. (a) False (b) True
32. 32.True or false: a slide switch slides side to side. (a) True (b) False
33. 33.💡 6 identical bulbs are in parallel and each one takes 0.5 A. What total current (in amperes) comes from the battery? =
34. 34.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) by Wi-Fi (b) in parallel (c) not joined (d) in series
35. 35.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
36. 36.🔺 A current of 0.25 A flows when 2.5 V is joined across a resistor. What is its resistance (in ohms)?
37. 37.⚡ What does an electric toy car mainly change electricity into? (a) movement (b) light (c) sound (d) heat
38. 38.🧮 Three equal 150 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
39. 39.🔁 repeat 4 times { repeat 6 times { beep } }
    How many beeps are there?
40. 40.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)

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