Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 930 · 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 is joined to a 6 V battery through a 470 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) lights up (b) may burn out (c) does not light
2. 2.💡 A battery lights 5 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same
3. 3.What does a buzzer do? (a) senses how bright it is (b) stores a little charge (c) glows using little power (d) beeps for an alarm
4. 4.🔁 Is the circuit closed or open if the bulb is unscrewed? (a) closed (b) open
5. 5.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a graphite rod across the gap. Does the bulb glow? (a) No (b) Yes
6. 6.True or false: a candle has no microcontroller inside. (a) False (b) True
7. 7.True or false: an LED blows if current is high. (a) True (b) False
8. 8.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
9. 9.🧮 Adding another resistor in series makes the total resistance … (a) bigger (b) smaller (c) zero (d) stay the same
10. 10.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a plastic ruler. Does the bulb glow? (a) No (b) Yes
11. 11.📏 Voltmeter or ammeter: which one measures voltage? (a) voltmeter (b) ammeter
12. 12.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 10 minutes?
13. 13.🤖 Does a digital thermometer usually have a microcontroller inside? (a) Yes (b) No
14. 14.⏱️ repeat 9 times { buzzer ON; wait 300 ms; buzzer OFF; wait 700 ms }
    How many milliseconds does this take in all?
15. 15.⚠️ Is it safe to touch a fallen wire? (a) safe (b) not safe
16. 16.💡 An LED is joined to a 3 V battery through a 1000 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) does not light (b) may burn out (c) lights up
17. 17.⏱️ How many milliseconds is a wait of 1.2 seconds?
18. 18.📶 Digital or analog: HIGH or LOW only? (a) digital (b) analog
19. 19.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) post it online (b) type it all in (c) share it with friends (d) ask a parent first
20. 20.⏱️ How many milliseconds are in 1 second? (a) 60 (b) 10 (c) 100 (d) 1000
21. 21.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a ceramic cup. Does the bulb glow? (a) No (b) Yes
22. 22.Which of these mainly gives out heat? (a) a street light (b) a mixer grinder (c) an exhaust fan (d) an electric iron
23. 23.✏️ Why do engineers draw circuits with symbols? (a) symbols are heavier (b) quick and clear for all (c) to hide the circuit (d) to make it colourful
24. 24.⚡ Power tells us … (a) the colour of light (b) the length of a wire (c) the size of a cell (d) energy used each second
25. 25.🔁 repeat 3 times { repeat 2 times { beep } }
    How many beeps are there?
26. 26.Which of these is true of a series circuit? (a) many paths for current (b) bulbs share the voltage (c) each gets the full volts (d) one out, the rest glow
27. 27.🔘 Which kind of switch slides side to side? (a) a push button (b) a tilt switch (c) a toggle switch (d) a slide switch
28. 28.Which of these is a conductor? (a) a ceramic cup (b) a metal paper clip (c) a rubber band (d) a woollen thread
29. 29.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) never (b) only when both are OFF (c) only when both are ON (d) when either is ON
30. 30.🧮 Resistors of 20 Ω, 10 Ω, 100 Ω and 220 Ω are joined in series. What is the total resistance (in ohms)?
31. 31.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open
32. 32.True or false: a steel spoon is an insulator. (a) True (b) False
33. 33.⚡ A fan changes electrical energy mainly into which kind of energy? (a) light energy (b) chemical energy (c) movement energy (d) sound energy
34. 34.True or false: “used in house wiring” is true of a series circuit. (a) True (b) False
35. 35.Which of these is a conductor? (a) a cotton thread (b) a copper wire (c) a wooden stick (d) a plastic straw
36. 36.✏️ In a circuit diagram, which part is drawn as triangle against a bar? (a) capacitor (b) motor (c) wire (d) diode
37. 37.🔁 total = 0
    for i = 1 to 9 { total = total + i }
    What is total at the end?
38. 38.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
39. 39.True or false: to switch off empty rooms saves electricity. (a) False (b) True
40. 40.🔘 What does a switch do in a circuit? (a) stores current (b) changes the voltage (c) opens or closes the loop (d) makes electricity

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