Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 986 · 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.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) series (b) parallel
2. 2.💡 6 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. All the bulbs are in place. Does bulb 1 glow? (a) No (b) Yes
3. 3.⚡ A device works on 5 V and takes 0.25 A. What is its power (in watts)? =
4. 4.Which drawing is the symbol for a battery? (a) two or more cell symbols (b) a long and a short line (c) a circle with M inside (d) triangle against a bar
5. 5.⚠️ Is it safe to build with an adult near? (a) safe (b) not safe
6. 6.Which job needs an LED? (a) open a gate to 90° (b) show the temperature (c) spin a robot’s wheels (d) show a status light
7. 7.Which drawing is the symbol for a motor? (a) a circle with M inside (b) a circle with A inside (c) triangle, bar and arrows (d) a small empty box
8. 8.🔁 Is the circuit closed or open if all wires are joined? (a) open (b) closed
9. 9.True or false: “own switch for each bulb” is true of a series circuit. (a) True (b) False
10. 10.⚡ What does a siren mainly change electricity into? (a) light (b) movement (c) sound (d) heat
11. 11.🧮 A 47 Ω resistor is joined in series with two equal 470 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
12. 12.Which of these is a conductor? (a) a brass key (b) a dry cork (c) a rubber eraser (d) a rubber band
13. 13.🔋 3 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
14. 14.📶 Digital or analog: how loud a sound is? (a) digital (b) analog
15. 15.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 60 (c) 100 (d) 1000
16. 16.🧩 Which component glows using little power? (a) motor (b) LDR (c) thermistor (d) LED
17. 17.Which job needs a pump? (a) beep an alarm (b) spin a robot’s wheels (c) open a gate to 90° (d) move water to plants
18. 18.🔁 x = 1
    repeat 5 times { x = x × 2 }
    What is x at the end?
19. 19.🔍 Which is the odd one out? (a) share camera links (b) turn off unused gadgets (c) keep factory passwords (d) tap unknown app links
20. 20.🔋 Cells joined + to − in a row (series) give … (a) a smaller voltage (b) no voltage (c) the same voltage (d) a bigger voltage
21. 21.🧭 Which part of a microcontroller board connect sensors and LEDs? (a) the pins (b) the reset button (c) the USB port (d) the power LED
22. 22.🔘 Which kind of switch slides side to side? (a) a push button (b) a slide switch (c) a tilt switch (d) a reed switch
23. 23.True or false: an LDR senses how bright it is. (a) False (b) True
24. 24.🌈 A resistor has the colour bands brown, black, black. What is its value (in ohms)?
25. 25.What does a resistor do? (a) makes a beeping sound (b) beeps for an alarm (c) lets current go one way (d) limits the current
26. 26.🌈 A gold fourth band on a resistor means the value may be off by … (a) 0 % (b) 5 % (c) 25 % (d) 50 %
27. 27.📏 Which unit measures current? (a) ampere (A) (b) ohm (Ω) (c) volt (V) (d) watt (W)
28. 28.🤖 if (temperature > 38) { show “Hot” } else if (temperature > 18) { show “Warm” } else { show “Cool” }
    The temperature is 32 °C. What is shown? (a) Warm (b) Cool (c) Hot
29. 29.🌈 In the resistor colour code, which number does green stand for?
30. 30.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to a 3.5 V supply. What current flows (in mA)?
31. 31.🔌 Is a ceramic cup a conductor or an insulator? (a) an insulator (b) a conductor
32. 32.🔢 To run one loop of a plant-watering program, which comes first: “read the soil sensor” or “switch the pump on/off”? (a) switch the pump on/off (b) read the soil sensor
33. 33.🧩 Which part changes electrical energy into movement? (a) a fuse (b) a resistor (c) an LED (d) a motor
34. 34.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave the TV on standby (c) unplug idle chargers (d) run fans in empty rooms
35. 35.🔐 Is it a good or a risky habit to reuse one password? (a) risky habit (b) good habit
36. 36.🌈 A resistor has the colour bands violet, violet, yellow. What is its value in kilo-ohms (kΩ)? =
37. 37.🔍 Which sensor would you use to measure classroom noise? (a) a rain sensor (b) a sound sensor (c) a soil moisture sensor (d) a light sensor
38. 38.⚠️ Is it safe to touch a switch when wet? (a) safe (b) not safe
39. 39.Which of these is safe? (a) throw cells in a fire (b) open a phone charger (c) touch a fallen wire (d) keep drinks far away
40. 40.⚡ What does a loudspeaker mainly change electricity into? (a) movement (b) light (c) heat (d) sound

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