Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 17 · 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.🔢 To get a sensor reading onto a phone, which is the LAST step? (a) the sensor measures (b) the app shows it (c) it is sent by Wi-Fi (d) the cloud stores it
2. 2.Which of these is an insulator? (a) a steel coin (b) a steel spoon (c) aluminium foil (d) a rubber band
3. 3.🔘 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) No (b) Yes
4. 4.Which of these is safe? (a) poke things in a socket (b) touch a switch when wet (c) use small battery cells (d) throw cells in a fire
5. 5.💡 2 identical bulbs are joined in series with a 2 V battery (ideal wires). How many volts does each bulb get? =
6. 6.💡 What does LED stand for? (a) large electric dial (b) light energy dial (c) light-emitting diode (d) low energy device
7. 7.⚠️ Is it safe to poke things in a socket? (a) safe (b) not safe
8. 8.Which of these is measured in watts (W)? (a) the flow of charge (b) power (c) current (d) the push of a cell
9. 9.⚠️ Someone is getting a shock and is still touching a wire. What should you do? (a) wait and watch (b) pour water on them (c) shout for an adult (d) pull them by the hand
10. 10.🔋 Does a wind turbine give electricity or use electricity? (a) uses electricity (b) gives electricity
11. 11.True or false: a mixer grinder mainly gives out heat. (a) True (b) False
12. 12.🔦 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 paper strip. Does the bulb glow? (a) Yes (b) No
13. 13.🔍 Which sensor would you use to keep an incubator warm? (a) a soil moisture sensor (b) a temperature sensor (c) a light sensor (d) a rain sensor
14. 14.🔺 A 12 V supply is joined across a 300 Ω resistor. What current flows (in milliamperes, mA)?
15. 15.What does the microcontroller do? (a) carries the data (b) acts on a command (c) reads values, decides (d) shows data to you
16. 16.True or false: the voltmeter is joined across a part. (a) True (b) False
17. 17.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) tell it your passwords (b) let strangers use it (c) mute it when not in use (d) put it in the bathroom
18. 18.🔍 Which is the odd one out? (a) a night lamp (b) a tube light (c) a siren (d) a traffic signal
19. 19.🔘 Which kind of switch springs back when let go? (a) a tilt switch (b) a push button (c) a reed switch (d) a toggle switch
20. 20.Which of these is the output? (a) a light level reading (b) decide if soil is dry (c) an alert on the phone (d) count button presses
21. 21.True or false: the voltmeter is joined in series. (a) True (b) False
22. 22.True or false: a plastic ruler is an insulator. (a) True (b) False
23. 23.True or false: a microcontroller uses very little power. (a) False (b) True
24. 24.🔢 To plan an electronics project, what comes right after “pick a problem to solve”? (a) build it with an adult (b) test it and fix it (c) list inputs and outputs (d) draw the circuit diagram
25. 25.🤖 if (light < 200) { lamp ON } else { lamp OFF }
    The light sensor reads 206. What happens? (a) lamp ON (b) lamp OFF
26. 26.🔢 To get a sensor reading onto a phone, which is the FIRST step? (a) the cloud stores it (b) it is sent by Wi-Fi (c) the sensor measures (d) the board reads it
27. 27.🔺 A current of 0.1 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
28. 28.True or false: a hand pump usually has a microcontroller inside. (a) False (b) True
29. 29.🌈 A resistor has the colour bands blue, violet, brown. What is its value (in ohms)?
30. 30.Which of these saves electricity? (a) leave the TV on standby (b) leave fridge door open (c) close the fridge quickly (d) run fans in empty rooms
31. 31.🔘 When a switch is ON, the circuit is … (a) closed (b) broken (c) open (d) cut
32. 32.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they keep glowing (b) they all go out (c) they get dimmer (d) they explode
33. 33.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
34. 34.🧩 Which part changes electrical energy into movement? (a) a fuse (b) an LED (c) a resistor (d) a motor
35. 35.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 1024 (b) 1000 (c) 10 (d) 100
36. 36.💡 In a series circuit, how many paths does the current have? (a) none (b) one for each bulb (c) one (d) two
37. 37.🔍 Which sensor would you use to open blinds at sunrise? (a) a motion sensor (b) a light sensor (c) a soil moisture sensor (d) a distance sensor
38. 38.Which of these mainly gives out heat? (a) a ceiling fan (b) an LED lamp (c) a toaster (d) a night lamp
39. 39.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
40. 40.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets bigger (b) becomes zero (c) gets smaller (d) stays the same

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