Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 475 · 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.🧮 Resistors of 100 Ω, 47 Ω, 22 Ω and 220 Ω are joined in series. What is the total resistance (in ohms)?
2. 2.🗺️ In an input → process → output plan, is “a motion sensor signal” the input, the process or the output? (a) input (b) output (c) process
3. 3.⚠️ About how many volts do home sockets in India supply? (a) 9 V (b) 1.5 V (c) 230 V (d) 12 V
4. 4.🧩 Which component limits the current? (a) buzzer (b) resistor (c) fuse (d) potentiometer
5. 5.🔺 A current of 40 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
6. 6.📏 In the water-pipe picture of a circuit, current is like … (a) the pipe colour (b) the water pressure (c) a narrow pipe (d) the flow of water
7. 7.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) neither part (c) the if part (d) the else part
8. 8.Which of these is true of a series circuit? (a) used in house wiring (b) a break stops every bulb (c) many paths for current (d) each gets the full volts
9. 9.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 29 Ω resistor? (a) orange-white-black (b) red-white-brown (c) white-red-black (d) red-white-black
10. 10.True or false: the ammeter is joined across a part. (a) False (b) True
11. 11.True or false: a paper strip is a conductor. (a) False (b) True
12. 12.True or false: “count button presses” is the input. (a) False (b) True
13. 13.💡 In a series circuit, how many paths does the current have? (a) two (b) none (c) one for each bulb (d) one
14. 14.🔺 In the V-I-R triangle, how do we find V? (a) V = I + R (b) V = I × R (c) V = I ÷ R (d) V = R ÷ I
15. 15.Which of these is an IoT device? (a) a battery torch (b) a plain wall switch (c) a smart energy meter (d) a plain table fan
16. 16.🧩 Which part changes electrical energy into movement? (a) a resistor (b) an LED (c) a fuse (d) a motor
17. 17.🔺 A current of 0.2 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
18. 18.📏 How many ohms make 1 kilo-ohm (kΩ)? (a) 10 (b) 1024 (c) 1000 (d) 100
19. 19.⚡ A solar panel changes which kind of energy into electricity? (a) wind energy (b) light energy (c) chemical energy (d) sound energy
20. 20.🌐 What does IoT stand for? (a) Inside of Toys (b) Internet of Things (c) Internet of Talk (d) Input of Tools
21. 21.What does the actuator do? (a) shows data to you (b) reads values, decides (c) acts on a command (d) measures the real world
22. 22.🔍 An object is 255 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
23. 23.Which of these wastes electricity? (a) use LED lamps (b) set the AC to 24 °C (c) close the fridge quickly (d) leave the TV on standby
24. 24.🔺 A current of 0.25 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
25. 25.🧮 Two equal 40 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
26. 26.🔋 What should you do with used-up cells? (a) throw them in a fire (b) bury them in soil (c) cut them open (d) give them for recycling
27. 27.🌐 A soil sensor sends a reading to an app every 5 minutes. How many readings arrive in 3 hours?
28. 28.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) True (b) False
29. 29.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
30. 30.🔁 In an old-style bulb, which thin wire glows when current flows? (a) the glass (b) the filament (c) the switch (d) the base
31. 31.📏 How many milliamperes (mA) is 0.68 A?
32. 32.🔺 A current of 20 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
33. 33.📏 How many milliamperes (mA) is 1.1 A?
34. 34.🧾 One “unit” on an electricity bill is … (a) 1 kilowatt-hour (kWh) (b) 1 ampere (c) 1 volt (d) 1 watt
35. 35.💡 An LED is joined to a 9 V battery through a 1000 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) does not light (b) lights up (c) may burn out
36. 36.📏 How many milliamperes (mA) make 1 ampere? (a) 10 (b) 1000 (c) 60 (d) 100
37. 37.🤖 Microcontroller or laptop: which one runs many apps at once? (a) laptop (b) microcontroller
38. 38.🧩 A capacitor in a circuit can … (a) spin a wheel (b) make light (c) measure heat (d) store charge briefly
39. 39.🧮 Resistors of 68 Ω, 68 Ω, 22 Ω and 10 Ω are joined in series. What is the total resistance (in ohms)?
40. 40.🔁 repeat 5 times { repeat 5 times { beep } }
    How many beeps are there?

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