Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 742 · 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: to poke things in a socket is safe. (a) True (b) False
2. 2.🔍 Which is the odd one out? (a) share the Wi-Fi key (b) cover unused cameras (c) share camera links (d) post your live location
3. 3.Which of these is true of a parallel circuit? (a) one bulb out, all go out (b) each gets the full volts (c) a single current path (d) bulbs share the voltage
4. 4.🔘 A cell, a bulb and switches A and B are joined one after another in a single loop (series). A is OFF and B is OFF. Does the bulb glow? (a) Yes (b) No
5. 5.💡 4 identical bulbs are joined in parallel across a 4.5 V battery (ideal wires). How many volts does each bulb get? =
6. 6.🔋 Does a bicycle dynamo give electricity or use electricity? (a) uses electricity (b) gives electricity
7. 7.🤖 if (temperature > 32) { fan ON } else { fan OFF }
   The temperature sensor reads 24 °C. What happens? (a) fan ON (b) fan OFF
8. 8.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a plastic ruler across the gap. Does the bulb glow? (a) Yes (b) No
9. 9.🔘 A bulb and a cell are joined through 4 switches one after another in a single loop (series). What is the smallest number of switches that must be ON to light the bulb?
10. 10.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
11. 11.True or false: to set a strong password is a risky habit. (a) False (b) True
12. 12.✏️ In a circuit diagram, which part is drawn as a long and a short line? (a) switch (b) motor (c) LED (d) cell
13. 13.🔐 Why install updates on IoT devices? (a) they change the colour (b) they delete the Wi-Fi (c) they fix security holes (d) they make it heavier
14. 14.🌐 Is a plain table fan an IoT device? (a) an IoT device (b) not an IoT device
15. 15.🧩 Which part changes electrical energy into sound? (a) a resistor (b) a diode (c) a capacitor (d) a buzzer
16. 16.Which job needs a distance sensor? (a) stop a robot near walls (b) start a fan when hot (c) warn of a gas leak (d) switch on lamps at dusk
17. 17.📶 On a 5 V board, a pin set HIGH gives about … (a) 230 V (b) 0 V (c) 50 V (d) 5 V
18. 18.Which of these means the circuit is closed? (a) a wire is cut (b) the switch is OFF (c) a cell is taken out (d) the loop is complete
19. 19.💡 Does it save or waste electricity to use old filament bulbs? (a) saves electricity (b) wastes electricity
20. 20.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 1 minute?
21. 21.True or false: a diode is a resistance knob. (a) False (b) True
22. 22.🌈 In the resistor colour code, which number does red stand for?
23. 23.💡 A red LED uses 2 V and should get 25 mA. It runs from a 9 V supply. What resistor (in ohms) is needed in series?
24. 24.Which of these wastes electricity? (a) unplug idle chargers (b) switch off empty rooms (c) leave fridge door open (d) set the AC to 24 °C
25. 25.🤖 Microcontroller or laptop: which one needs much more power? (a) laptop (b) microcontroller
26. 26.🔘 A cell, a bulb and switches A, B and C are joined one after another in a single loop (series). A is ON, B is ON and C is ON. Does the bulb glow? (a) Yes (b) No
27. 27.🌐 Each reading a sensor sends is 10 bytes. How many bytes do 190 readings take?
28. 28.🔺 A 10 V supply is joined across a 5 Ω resistor. What current flows (in amperes)? =
29. 29.Which of these means the circuit is open? (a) the loop is complete (b) a cell is taken out (c) all wires are joined (d) the switch is ON
30. 30.True or false: to water a dry plant, use a gas sensor. (a) False (b) True
31. 31.💡 In a series circuit, how many paths does the current have? (a) none (b) one (c) two (d) one for each bulb
32. 32.🔺 A 3 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
33. 33.True or false: to use daylight to read saves electricity. (a) False (b) True
34. 34.Which of these is true of a parallel circuit? (a) bulbs share the voltage (b) a single current path (c) many paths for current (d) a break stops every bulb
35. 35.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) + (positive) (b) − (negative)
36. 36.🔁 total = 0
    for i = 1 to 6 { total = total + i }
    What is total at the end?
37. 37.🔍 Which is the odd one out? (a) post your live location (b) reuse one password (c) accept every permission (d) set up with a parent
38. 38.True or false: “check if temp > 30” is the process. (a) False (b) True
39. 39.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) motor (b) ammeter (c) cell (d) wire
40. 40.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) True (b) False

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