Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 664 · 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.🔍 Which is the odd one out? (a) a safety pin (b) a rubber eraser (c) a copper wire (d) a brass key
2. 2.🔗 Series or parallel circuit: “many paths for current”? (a) series (b) parallel
3. 3.📏 Which unit measures resistance? (a) ampere (A) (b) volt (V) (c) ohm (Ω) (d) watt (W)
4. 4.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 22) { show “Warm” } else { show “Cool” }
   The temperature is 41 °C. What is shown? (a) Warm (b) Cool (c) Hot
5. 5.🤖 if (light < 400) { lamp ON } else { lamp OFF }
   The light sensor reads 334. What happens? (a) lamp ON (b) lamp OFF
6. 6.🔍 Which sensor would you use to spot someone walking in? (a) a sound sensor (b) a light sensor (c) a motion sensor (d) a rain sensor
7. 7.Which of these mainly makes sound? (a) a traffic signal (b) an electric drill (c) a buzzer (d) a night lamp
8. 8.True or false: a resistor has coloured bands. (a) True (b) False
9. 9.🔌 Is a metal paper clip a conductor or an insulator? (a) a conductor (b) an insulator
10. 10.⏱️ repeat 4 times { buzzer ON; wait 700 ms; buzzer OFF; wait 700 ms }
    How many milliseconds does this take in all?
11. 11.🔍 Which is the odd one out? (a) keep drinks far away (b) poke things in a socket (c) fly a kite near wires (d) climb an electric pole
12. 12.🌐 A soil sensor sends a reading to an app every 20 minutes. How many readings arrive in 6 hours?
13. 13.True or false: a push button works only while pressed. (a) True (b) False
14. 14.🗺️ Before building a project, what should you write down first? (a) inputs and outputs (b) the final price (c) the box colour (d) nothing at all
15. 15.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
16. 16.🔍 Which sensor would you use to switch on lamps at dusk? (a) a rain sensor (b) a light sensor (c) a distance sensor (d) a motion sensor
17. 17.🧩 Which part changes electrical energy into sound? (a) a diode (b) a capacitor (c) a resistor (d) a buzzer
18. 18.🔺 In the V-I-R triangle, how do we find I? (a) I = V × R (b) I = R ÷ V (c) I = V ÷ R (d) I = V + R
19. 19.🔍 Which is the odd one out? (a) share only needed data (b) read app permissions (c) reuse one password (d) turn off unused gadgets
20. 20.🔺 In the V-I-R triangle, how do we find V? (a) V = R ÷ I (b) V = I ÷ R (c) V = I × R (d) V = I + R
21. 21.🔍 Which is the odd one out? (a) close the fridge quickly (b) use old filament bulbs (c) use daylight to read (d) unplug idle chargers
22. 22.True or false: a potentiometer limits the current. (a) True (b) False
23. 23.🔐 Is it a good or a risky habit to log out of shared phones? (a) risky habit (b) good habit
24. 24.🤖 Which is a safe power source for a beginner microcontroller board? (a) a 230 V cable (b) a wall socket directly (c) USB or a 9 V battery (d) bare mains wires
25. 25.🔍 Which sensor would you use to switch on with a clap? (a) a distance sensor (b) a soil moisture sensor (c) a temperature sensor (d) a sound sensor
26. 26.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 280 and motion is not detected (false). What happens? (a) porch lamp ON (b) porch lamp OFF
27. 27.🔋 What is a battery? (a) a kind of bulb (b) two or more cells joined (c) one single wire (d) a switch with a lid
28. 28.💡 In a series circuit, how many paths does the current have? (a) two (b) one for each bulb (c) none (d) one
29. 29.🤖 if (light < 400) { lamp ON } else { lamp OFF }
    The light sensor reads 368. What happens? (a) lamp OFF (b) lamp ON
30. 30.⚡ Which formula gives electric power? (a) P = V + I (b) P = V ÷ I (c) P = I ÷ V (d) P = V × I
31. 31.Which of these is not an IoT device? (a) a fitness band with app (b) a Wi-Fi doorbell camera (c) a Wi-Fi weather station (d) a plain wall switch
32. 32.⚡ A device works on 9 V and takes 0.5 A. What is its power (in watts)? =
33. 33.💡 Does it save or waste electricity to unplug idle chargers? (a) wastes electricity (b) saves electricity
34. 34.🔁 repeat 3 times { repeat 4 times { beep } }
    How many beeps are there?
35. 35.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) only one (b) none (c) it does not matter (d) both of them
36. 36.💡 3 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 2 is taken out of its holder. Does bulb 1 glow? (a) Yes (b) No
37. 37.🔺 A current of 2 A flows through a 15 Ω resistor. What is the voltage across it (in volts)? =
38. 38.Which of these is the process? (a) compare with a limit (b) an LED lights up (c) a motion sensor signal (d) the fan starts
39. 39.True or false: voltage is measured in volts (V). (a) False (b) True
40. 40.Which of these mainly gives out heat? (a) a buzzer (b) a torch (c) a doorbell (d) a water heater

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