Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 976 · 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 of these is the input? (a) count button presses (b) the fan starts (c) a buzzer beeps (d) a motion sensor signal
2. 2.True or false: the ammeter measures current. (a) False (b) True
3. 3.Which of these mainly gives out heat? (a) an LED lamp (b) a loudspeaker (c) a street light (d) a water heater
4. 4.🧮 Resistors of 50 Ω, 20 Ω, 330 Ω and 220 Ω are joined in series. What is the total resistance (in ohms)?
5. 5.💡 A battery lights 5 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) the same (c) dimmer
6. 6.🔌 Which metal is used for most electric wires at home? (a) rubber (b) plastic (c) copper (d) glass
7. 7.⚡ What does an electric kettle mainly change electricity into? (a) light (b) sound (c) heat (d) movement
8. 8.True or false: many long-short pairs is the symbol for a battery. (a) False (b) True
9. 9.🔍 Which sensor would you use to start a fan when hot? (a) a temperature sensor (b) a gas sensor (c) a soil moisture sensor (d) a motion sensor
10. 10.True or false: triangle, bar and arrows is the symbol for an LED. (a) True (b) False
11. 11.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
12. 12.📏 Which unit measures resistance? (a) ohm (Ω) (b) volt (V) (c) watt (W) (d) ampere (A)
13. 13.💡 Why does an LED need a resistor in series? (a) to make it brighter (b) to change its colour (c) to limit the current (d) to store charge
14. 14.True or false: if a wire is cut, the circuit is closed and current flows. (a) False (b) True
15. 15.📶 How many states can a digital pin have? (a) ten (b) one (c) two (d) a thousand
16. 16.🧩 Which component beeps for an alarm? (a) fuse (b) buzzer (c) diode (d) motor
17. 17.⏱️ loop forever { LED ON; wait 200 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 5 seconds?
18. 18.✏️ In a circuit diagram, which part is drawn as two equal parallel lines? (a) switch (b) voltmeter (c) battery (d) capacitor
19. 19.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = I ÷ V (c) P = V + I (d) P = V × I
20. 20.Which of these is an IoT device? (a) a Wi-Fi smart plug (b) a wind-up clock (c) a plain wall switch (d) a plain table fan
21. 21.True or false: to spot someone walking in, use a sound sensor. (a) True (b) False
22. 22.🔁 What does a variable do in a program? (a) joins two wires (b) stores a value (c) blinks an LED (d) measures light
23. 23.🔁 count = 4
    repeat 3 times { count = count + 2 }
    What is count at the end?
24. 24.🔁 total = 0
    for i = 1 to 12 { total = total + i }
    What is total at the end?
25. 25.🔺 A 10 V supply is joined across a 500 Ω resistor. What current flows (in milliamperes, mA)?
26. 26.🧾 A family uses 170 units of electricity in a month and each unit costs ₹9. What is the bill (in ₹)?
27. 27.True or false: on a cell, “usually the red wire” means the − (negative) end. (a) False (b) True
28. 28.🔍 Which is the odd one out? (a) set the AC to 24 °C (b) run fans in empty rooms (c) unplug idle chargers (d) close the fridge quickly
29. 29.🔍 Which is the odd one out? (a) open a phone charger (b) build with an adult near (c) stop if a part gets hot (d) take cells out after use
30. 30.🧩 Which component limits the current? (a) LDR (b) resistor (c) thermistor (d) transistor
31. 31.True or false: on an LED, the round-side leg is the cathode (−). (a) False (b) True
32. 32.💡 What does LED stand for? (a) large electric dial (b) light energy dial (c) light-emitting diode (d) low energy device
33. 33.💡 Does it save or waste electricity to leave the TV on standby? (a) wastes electricity (b) saves electricity
34. 34.⏱️ loop forever { LED ON; wait 400 ms; LED OFF; wait 1600 ms }
    How many times does the LED blink in 2 seconds?
35. 35.🤖 Does a spinning top usually have a microcontroller inside? (a) Yes (b) No
36. 36.⚡ What do we call a flow of electric charge through a wire? (a) electric current (b) a magnet (c) friction (d) sound
37. 37.🧩 A capacitor in a circuit can … (a) spin a wheel (b) make light (c) store charge briefly (d) measure heat
38. 38.🌐 In an IoT system, which part shows data to you? (a) phone app (b) sensor (c) actuator (d) Wi-Fi
39. 39.🔌 Is a dry cork a conductor or an insulator? (a) a conductor (b) an insulator
40. 40.🔺 A current of 0.1 A flows when 1 V is joined across a resistor. What is its resistance (in ohms)?

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