Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 150 · 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.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 7 HIGH
   set pin 7 LOW
   Is the LED ON or OFF at the end? (a) ON (b) OFF
2. 2.True or false: “one bulb out, all go out” is true of a series circuit. (a) False (b) True
3. 3.Which of these is measured in volts (V)? (a) current (b) how much a part resists (c) power (d) the push of a cell
4. 4.🔺 A current of 0.5 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
5. 5.✏️ In a circuit diagram, which part is drawn as a straight line? (a) switch (b) bulb (c) resistor (d) wire
6. 6.🤖 Which is a safe power source for a beginner microcontroller board? (a) a wall socket directly (b) bare mains wires (c) a 230 V cable (d) USB or a 9 V battery
7. 7.⏱️ loop forever { LED ON; wait 1000 ms; LED OFF; wait 950 ms }
   How many milliseconds does one blink (ON + OFF) take?
8. 8.🧩 Which part changes electrical energy into movement? (a) an LED (b) a motor (c) a resistor (d) a fuse
9. 9.🌈 In the resistor colour code, which number does orange stand for?
10. 10.What does a diode do? (a) beeps for an alarm (b) stores a little charge (c) lets current go one way (d) makes things spin
11. 11.💡 An LED is joined to a 5 V battery with no resistor; the leg next to the flat edge of its rim goes to the − side. What happens? (a) lights up (b) may burn out (c) does not light
12. 12.💡 4 identical bulbs are joined in series with an 8 V battery (ideal wires). How many volts does each bulb get? =
13. 13.⚡ What does a loudspeaker mainly change electricity into? (a) heat (b) sound (c) light (d) movement
14. 14.Which of these mainly gives out heat? (a) a tube light (b) an exhaust fan (c) a rice cooker (d) a school bell
15. 15.💡 In a series circuit, how many paths does the current have? (a) none (b) two (c) one (d) one for each bulb
16. 16.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
17. 17.🔌 Is a copper wire a conductor or an insulator? (a) a conductor (b) an insulator
18. 18.True or false: a reed switch closes near a magnet. (a) False (b) True
19. 19.⚙️ Which actuator would you use to show the temperature? (a) a display (b) a buzzer (c) a servo motor (d) a motor
20. 20.🔍 Which is the odd one out? (a) an LED lamp (b) a traffic signal (c) a night lamp (d) an electric iron
21. 21.⚡ A home appliance on the 230 V mains takes 8 A. What is its power (in watts)?
22. 22.Which of these mainly gives out light? (a) a water heater (b) a torch (c) an electric drill (d) a siren
23. 23.True or false: if all wires are joined, the circuit is closed and current flows. (a) True (b) False
24. 24.🧩 Which part changes electrical energy into sound? (a) a buzzer (b) a resistor (c) a capacitor (d) a diode
25. 25.True or false: “an alert on the phone” is the process. (a) True (b) False
26. 26.📏 Voltmeter or ammeter: which one is joined across a part? (a) ammeter (b) voltmeter
27. 27.🔢 To plan an electronics project, which comes first: “list inputs and outputs” or “draw the circuit diagram”? (a) draw the circuit diagram (b) list inputs and outputs
28. 28.🌈 A resistor has the colour bands green, violet, red. What is its value (in ohms)?
29. 29.🤖 What is a microcontroller? (a) a kind of bulb (b) a type of battery (c) a big desktop computer (d) a computer on one chip
30. 30.🔺 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
31. 31.🔢 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
32. 32.🔌 Most metals are good … (a) conductors (b) magnets only (c) insulators (d) batteries
33. 33.🧮 Two resistors in parallel give a total that is … (a) their sum (b) more than either one (c) always zero (d) less than either one
34. 34.True or false: to post your live location is a risky habit. (a) False (b) True
35. 35.Which job needs an LED? (a) beep an alarm (b) open a gate to 90° (c) show a status light (d) move water to plants
36. 36.🔁 repeat 2 times { repeat 2 times { beep } }
    How many beeps are there?
37. 37.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) in series (b) in parallel (c) not joined (d) by Wi-Fi
38. 38.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
39. 39.True or false: if a wire is cut, the circuit is closed and current flows. (a) False (b) True
40. 40.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)

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