Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 901 · 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.⚠️ Is it safe to poke things in a socket? (a) safe (b) not safe
2. 2.🔍 Which is the odd one out? (a) switch off empty rooms (b) leave fridge door open (c) leave the TV on standby (d) run fans in empty rooms
3. 3.True or false: a reed switch springs back when let go. (a) True (b) False
4. 4.True or false: “how bright a room is” is a digital signal. (a) False (b) True
5. 5.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) battery (b) resistor (c) LED (d) bulb
6. 6.🧭 Which part of a microcontroller board brings power and code? (a) the pins (b) the USB port (c) the main chip (d) the voltage regulator
7. 7.🔍 Which is the odd one out? (a) use daylight to read (b) switch off empty rooms (c) leave the TV on standby (d) use LED lamps
8. 8.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 93 Ω resistor? (a) orange-white-black (b) white-orange-black (c) white-orange-brown (d) brown-orange-black
9. 9.⚡ A solar panel changes which kind of energy into electricity? (a) wind energy (b) chemical energy (c) light energy (d) sound energy
10. 10.🔌 Which part of a screwdriver should an electrician hold? (a) the plastic handle (b) the steel shaft (c) the metal tip (d) the bare end
11. 11.💡 An LED is joined to a 6 V battery through a 220 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
12. 12.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 26) { show “Warm” } else { show “Cool” }
    The temperature is 21 °C. What is shown? (a) Cool (b) Warm (c) Hot
13. 13.🔁 Is the circuit closed or open if the switch is ON? (a) closed (b) open
14. 14.⚠️ Someone is getting a shock and is still touching a wire. What should you do? (a) pull them by the hand (b) shout for an adult (c) wait and watch (d) pour water on them
15. 15.Which of these is safe? (a) open a phone charger (b) touch a switch when wet (c) poke things in a socket (d) fly kites in open fields
16. 16.🔋 2 identical 1.5 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
17. 17.🔘 Two switches are in series. When does the bulb glow? (a) when both are OFF (b) when both are ON (c) never (d) when either is ON
18. 18.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
19. 19.True or false: a circle with a cross is the symbol for a resistor. (a) False (b) True
20. 20.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
21. 21.🔍 Which sensor would you use to measure classroom noise? (a) a gas sensor (b) a sound sensor (c) a motion sensor (d) a soil moisture sensor
22. 22.📏 How many kilowatts (kW) is 2150 W? =
23. 23.True or false: a reed switch closes near a magnet. (a) True (b) False
24. 24.🔁 repeat 5 times { repeat 6 times { beep } }
    How many beeps are there?
25. 25.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a copper wire across the gap. Does the bulb glow? (a) No (b) Yes
26. 26.Which of these is the input? (a) a buzzer beeps (b) count button presses (c) an LED lights up (d) a motion sensor signal
27. 27.True or false: to climb an electric pole is safe. (a) True (b) False
28. 28.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
29. 29.🔌 Is a buzzer an input or an output for a microcontroller? (a) output (b) input
30. 30.🔺 A 3 V supply is joined across a 6 Ω resistor. What current flows (in amperes)? =
31. 31.💡 An LED is joined to a 6 V battery with no 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
32. 32.🔁 x = 3
    repeat 1 time { x = x × 2 }
    What is x at the end?
33. 33.💡 2 identical bulbs are joined in series with a battery and a closed switch on the main wire. All the bulbs are in place. Does bulb 2 glow? (a) Yes (b) No
34. 34.✏️ In a circuit diagram, which part is drawn as a circle with a cross? (a) LED (b) bulb (c) switch (d) battery
35. 35.🗺️ In an input → process → output plan, is “a buzzer beeps” the input, the process or the output? (a) output (b) process (c) input
36. 36.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) diode (b) ammeter (c) battery (d) bulb
37. 37.🧮 Two equal 1000 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
38. 38.Which of these saves electricity? (a) use old filament bulbs (b) run fans in empty rooms (c) leave the TV on standby (d) switch off empty rooms
39. 39.True or false: a laptop uses very little power. (a) True (b) False
40. 40.🔢 To get a sensor reading onto a phone, which comes first: “it is sent by Wi-Fi” or “the board reads it”? (a) it is sent by Wi-Fi (b) the board reads it

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