Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 938 · 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.⚡ A 0.15 W device works on 1.5 V. What current does it take (in amperes)? =
2. 2.Which job is done by the reset button? (a) runs the program (b) connect sensors and LEDs (c) restarts the program (d) brings power and code
3. 3.🔋 Does a solar panel give electricity or use electricity? (a) gives electricity (b) uses electricity
4. 4.🔘 Which kind of switch stays where you flip it? (a) a toggle switch (b) a reed switch (c) a slide switch (d) a push button
5. 5.Which of these is an insulator? (a) a graphite rod (b) a plastic ruler (c) an iron nail (d) aluminium foil
6. 6.⏱️ How many milliseconds are in 1 second? (a) 10 (b) 100 (c) 1000 (d) 60
7. 7.🧩 Which component senses how bright it is? (a) thermistor (b) LED (c) capacitor (d) LDR
8. 8.Which of these is the process? (a) a buzzer beeps (b) a motion sensor signal (c) decide if soil is dry (d) a temperature reading
9. 9.🔺 A current of 0.25 A flows when 3 V is joined across a resistor. What is its resistance (in ohms)?
10. 10.⚙️ What is an actuator? (a) a program (b) a battery (c) a sensor (d) an output that acts
11. 11.🔐 Is it a good or a risky habit to set a strong password? (a) good habit (b) risky habit
12. 12.🔍 Which is the odd one out? (a) a doorbell (b) a loudspeaker (c) a siren (d) a tube light
13. 13.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) a candle (c) an LED lamp (d) an oil lamp
14. 14.True or false: a small empty box is the symbol for a switch. (a) False (b) True
15. 15.🌐 In an IoT system, which part stores data online? (a) microcontroller (b) cloud server (c) phone app (d) Wi-Fi
16. 16.🌐 A weather station sends one reading every 60 seconds. How many readings does it send in 6 minutes?
17. 17.Which of these is a good habit? (a) accept every permission (b) tap unknown app links (c) set up with a parent (d) share camera links
18. 18.🔁 count = 9
    repeat 5 times { count = count + 8 }
    What is count at the end?
19. 19.True or false: a slide switch slides side to side. (a) False (b) True
20. 20.🔗 Series or parallel circuit: “a break stops every bulb”? (a) series (b) parallel
21. 21.💡 A battery lights 3 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) the same (b) brighter (c) dimmer
22. 22.🧩 Which part changes electrical energy into movement? (a) a fuse (b) a resistor (c) an LED (d) a motor
23. 23.Which of these is true of a parallel circuit? (a) one bulb out, all go out (b) one out, the rest glow (c) a break stops every bulb (d) a single current path
24. 24.True or false: the voltmeter measures voltage. (a) True (b) False
25. 25.⚠️ Is it safe to take cells out after use? (a) not safe (b) safe
26. 26.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
27. 27.True or false: to throw cells in a fire is safe. (a) False (b) True
28. 28.📏 How many ohms (Ω) is 3.5 kΩ?
29. 29.Which of these saves electricity? (a) leave the TV on standby (b) leave fridge door open (c) switch off empty rooms (d) run fans in empty rooms
30. 30.Which of these is measured in volts (V)? (a) current (b) the flow of charge (c) energy used each second (d) voltage
31. 31.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the else part (b) both parts (c) neither part (d) the if part
32. 32.🧮 Four equal 20 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
33. 33.True or false: a line lifted at a gap is the symbol for a battery. (a) False (b) True
34. 34.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a cotton thread. Does the bulb glow? (a) Yes (b) No
35. 35.⏱️ What does “wait 500 ms” do? (a) blinks 500 times (b) pauses for half a second (c) waits 500 seconds (d) turns the LED off
36. 36.🤖 if (light < 300 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 390 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
37. 37.True or false: a thermistor lets current go one way. (a) False (b) True
38. 38.🧮 A 1 V battery is joined to 6 Ω and 4 Ω resistors in series. What current flows (in amperes)? =
39. 39.🔢 To run one loop of a plant-watering program, which comes first: “read the soil sensor” or “wait a few seconds”? (a) read the soil sensor (b) wait a few seconds
40. 40.🌈 In the resistor colour code, which number does orange stand for?

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