Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 382 · 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: a plastic straw is an insulator. (a) True (b) False
2. 2.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the reset button (b) the USB port (c) the pins (d) the voltage regulator
3. 3.🔘 Which kind of switch works only while pressed? (a) a slide switch (b) a toggle switch (c) a reed switch (d) a push button
4. 4.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) neither part (c) the if part (d) the else part
5. 5.🔐 Who should decide which smart devices go in a child’s room? (a) nobody at all (b) the app’s adverts (c) a parent or guardian (d) an online stranger
6. 6.Which of these mainly gives out heat? (a) a night lamp (b) a table fan (c) an electric iron (d) an electric drill
7. 7.True or false: a microcontroller runs one small program. (a) True (b) False
8. 8.🧮 Resistors of 50 Ω, 220 Ω and 22 Ω are joined in series. What is the total resistance (in ohms)?
9. 9.True or false: to set a strong password is a good habit. (a) True (b) False
10. 10.💡 A battery lights 3 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) brighter (c) dimmer
11. 11.✏️ In a circuit diagram, which part is drawn as a small empty box? (a) resistor (b) battery (c) voltmeter (d) bulb
12. 12.⚡ Which formula gives electric power? (a) P = I ÷ V (b) P = V ÷ I (c) P = V + I (d) P = V × I
13. 13.⚙️ What is an actuator? (a) a battery (b) a program (c) an output that acts (d) a sensor
14. 14.True or false: to use mains for a project is not safe. (a) False (b) True
15. 15.🔺 A current of 40 mA flows through a 100 Ω resistor. What is the voltage across it (in volts)? =
16. 16.⏱️ A program says “wait 1250 ms”. How many seconds is that? =
17. 17.🔋 Does a battery give electricity or use electricity? (a) uses electricity (b) gives electricity
18. 18.Which of these mainly gives out light? (a) a room heater (b) an electric drill (c) a water heater (d) a torch
19. 19.🧾 A 1500 W appliance runs for 8 hours. How many units (kWh) of electricity does it use? =
20. 20.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an output (d) an input
21. 21.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) − (negative) (b) + (positive)
22. 22.True or false: a push button springs back when let go. (a) True (b) False
23. 23.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 26) { show “Warm” } else { show “Cool” }
    The temperature is 39 °C. What is shown? (a) Warm (b) Cool (c) Hot
24. 24.🔍 Which sensor would you use to spot someone walking in? (a) a motion sensor (b) a light sensor (c) a distance sensor (d) a soil moisture sensor
25. 25.True or false: “one bulb out, all go out” is true of a parallel circuit. (a) False (b) True
26. 26.Which job is done by the USB port? (a) brings power and code (b) restarts the program (c) connect sensors and LEDs (d) runs the program
27. 27.🧮 A 4.5 V battery is joined to 5 Ω and 4 Ω resistors in series. What current flows (in amperes)? =
28. 28.💡 What does LED stand for? (a) large electric dial (b) low energy device (c) light energy dial (d) light-emitting diode
29. 29.🔺 A 1.2 V supply is joined across a 6 Ω resistor. What current flows (in amperes)? =
30. 30.🔐 Is it a good or a risky habit to share the Wi-Fi key? (a) good habit (b) risky habit
31. 31.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 150 ms }
    How many times does the LED blink in 1 second?
32. 32.Which of these means the circuit is open? (a) all wires are joined (b) the loop is complete (c) the switch is ON (d) a cell is taken out
33. 33.🧮 Two resistors in parallel give a total that is … (a) their sum (b) more than either one (c) less than either one (d) always zero
34. 34.Which of these is the input? (a) compare with a limit (b) an alert on the phone (c) a temperature reading (d) count button presses
35. 35.What does a potentiometer do? (a) smooths a wobbly supply (b) is a resistance knob (c) limits the current (d) boosts a small signal
36. 36.🔁 total = 0
    for i = 1 to 7 { total = total + i }
    What is total at the end?
37. 37.🌈 A resistor has the colour bands green, green, red. What is its value (in ohms)?
38. 38.🧩 Which component has coloured bands? (a) buzzer (b) capacitor (c) resistor (d) thermistor
39. 39.🤖 Does a toy robot usually have a microcontroller inside? (a) No (b) Yes
40. 40.💡 Why is house wiring done in parallel? (a) to save copper only (b) to make bulbs dim (c) so all go off together (d) each gets full voltage

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