Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 693 · 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.🌐 In an IoT system, which part carries the data? (a) microcontroller (b) actuator (c) phone app (d) Wi-Fi
2. 2.🗺️ In an input → process → output plan, is “a button press” the input, the process or the output? (a) input (b) process (c) output
3. 3.⚡ A home appliance on the 230 V mains takes 5 A. What is its power (in watts)?
4. 4.True or false: a tilt switch works only while pressed. (a) True (b) False
5. 5.🧮 Resistors of 470 Ω and 150 Ω are joined in series. What is the total resistance (in ohms)?
6. 6.🤖 Does a plain wall switch usually have a microcontroller inside? (a) No (b) Yes
7. 7.True or false: on an LED, the round-side leg is the anode (+). (a) False (b) True
8. 8.True or false: to close a window in rain, use a rain sensor. (a) False (b) True
9. 9.🔁 count = 5
   while (count < 33) { count = count + 4 }
   How many times does the loop run?
10. 10.⏱️ A program says “wait 9250 ms”. How many seconds is that? =
11. 11.🧮 A 1.3 V battery is joined to 3 Ω and 10 Ω resistors in series. What current flows (in amperes)? =
12. 12.Which job needs a motor? (a) open a gate to 90° (b) spin a robot’s wheels (c) turn to an exact angle (d) show the temperature
13. 13.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) blinks 500 times (c) turns the LED off (d) pauses for half a second
14. 14.⚡ A device works on 24 V and takes 2 A. What is its power (in watts)? =
15. 15.🌈 In the resistor colour code, which number does black stand for?
16. 16.💡 Why does an LED need a resistor in series? (a) to change its colour (b) to store charge (c) to make it brighter (d) to limit the current
17. 17.⚡ A solar panel changes which kind of energy into electricity? (a) chemical energy (b) sound energy (c) wind energy (d) light energy
18. 18.🧩 Which part changes electrical energy into sound? (a) a resistor (b) a capacitor (c) a buzzer (d) a diode
19. 19.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) both of them (b) only one (c) none (d) it does not matter
20. 20.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets smaller (b) stays the same (c) becomes zero (d) gets bigger
21. 21.🧩 Which component smooths a wobbly supply? (a) buzzer (b) motor (c) capacitor (d) LDR
22. 22.🔁 What must there be for a current to flow? (a) a broken path (b) a plastic gap (c) a complete loop (d) one loose end
23. 23.🤖 Microcontroller or laptop: which one runs one small program? (a) microcontroller (b) laptop
24. 24.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) neither part (c) the else part (d) the if part
25. 25.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
26. 26.🔺 A current of 0.1 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
27. 27.🔘 Which kind of switch stays where you flip it? (a) a tilt switch (b) a slide switch (c) a toggle switch (d) a push button
28. 28.✏️ In a circuit diagram, which part is drawn as triangle against a bar? (a) battery (b) ammeter (c) bulb (d) diode
29. 29.🔍 Which is the odd one out? (a) share only needed data (b) share the Wi-Fi key (c) turn off unused gadgets (d) read app permissions
30. 30.🔺 A 0.6 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
31. 31.🌈 In the resistor colour code, which number does red stand for?
32. 32.🔺 A 12.5 V supply is joined across a 250 Ω resistor. What current flows (in milliamperes, mA)?
33. 33.🔢 To run one loop of a plant-watering program, what comes right after “read the soil sensor”? (a) switch the pump on/off (b) compare with the limit (c) wait a few seconds
34. 34.✏️ In a circuit diagram, which part is drawn as a plain rectangle? (a) battery (b) wire (c) resistor (d) voltmeter
35. 35.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) neither line (c) the shorter line (d) the longer line
36. 36.⚠️ Is it safe to fly a kite near wires? (a) safe (b) not safe
37. 37.True or false: to set the AC to 24 °C saves electricity. (a) False (b) True
38. 38.💡 Does it save or waste electricity to iron one shirt at a time? (a) wastes electricity (b) saves electricity
39. 39.🤖 Microcontroller or laptop: which one runs many apps at once? (a) microcontroller (b) laptop
40. 40.🔌 Is a motion sensor an input or an output for a microcontroller? (a) input (b) output

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