Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 206 · 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.🔁 Is the circuit closed or open if the loop is complete? (a) closed (b) open
2. 2.✏️ In a circuit diagram, which part is drawn as a line lifted at a gap? (a) LED (b) switch (c) motor (d) resistor
3. 3.🌈 A resistor has the colour bands green, white, orange. What is its value (in ohms)?
4. 4.🔋 What is a battery? (a) two or more cells joined (b) one single wire (c) a switch with a lid (d) a kind of bulb
5. 5.🔘 Which kind of switch closes near a magnet? (a) a tilt switch (b) a toggle switch (c) a push button (d) a reed switch
6. 6.Which of these is measured in ohms (Ω)? (a) current (b) how much a part resists (c) the flow of charge (d) the push of a cell
7. 7.🔍 Which is the odd one out? (a) use LED lamps (b) use daylight to read (c) leave fridge door open (d) close the fridge quickly
8. 8.🔋 On a cell, does “usually the black wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
9. 9.Which of these mainly makes movement? (a) a tube light (b) a buzzer (c) an electric iron (d) a ceiling fan
10. 10.True or false: “used in house wiring” is true of a parallel circuit. (a) True (b) False
11. 11.🧮 Adding another resistor in series makes the total resistance … (a) bigger (b) smaller (c) stay the same (d) zero
12. 12.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) True (b) False
13. 13.🔋 What should you do with used-up cells? (a) throw them in a fire (b) cut them open (c) bury them in soil (d) give them for recycling
14. 14.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) bulb (b) motor (c) switch (d) resistor
15. 15.🧩 Which component is a resistance knob? (a) resistor (b) motor (c) diode (d) potentiometer
16. 16.⏱️ repeat 3 times { buzzer ON; wait 100 ms; buzzer OFF; wait 100 ms }
    How many milliseconds does this take in all?
17. 17.🗺️ In an input → process → output plan, is “a temperature reading” the input, the process or the output? (a) process (b) input (c) output
18. 18.🌐 A soil sensor sends a reading to an app every 15 minutes. How many readings arrive in 6 hours?
19. 19.💡 Why does an LED need a resistor in series? (a) to limit the current (b) to make it brighter (c) to store charge (d) to change its colour
20. 20.🧩 Which component blows if current is high? (a) buzzer (b) LED (c) transistor (d) fuse
21. 21.Which of these saves electricity? (a) run fans in empty rooms (b) use old filament bulbs (c) unplug idle chargers (d) leave the TV on standby
22. 22.🔌 Is a servo motor an input or an output for a microcontroller? (a) input (b) output
23. 23.🔌 A gap of dry air between two wires acts as … (a) a cell (b) a conductor (c) an insulator (d) a switch that is ON
24. 24.🔺 A current of 1.5 A flows through a 12 Ω resistor. What is the voltage across it (in volts)? =
25. 25.True or false: to reuse one password is a good habit. (a) False (b) True
26. 26.💡 A blue LED uses 3 V and should get 10 mA. It runs from a 12 V supply. What resistor (in ohms) is needed in series?
27. 27.⚡ A solar panel changes which kind of energy into electricity? (a) wind energy (b) chemical energy (c) sound energy (d) light energy
28. 28.🌈 A resistor has the colour bands white, violet, black. What is its value (in ohms)?
29. 29.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) quick and clear for all (c) to hide the circuit (d) symbols are heavier
30. 30.🔋 How many 3 V cells must be joined in series to give 12 V?
31. 31.🔋 5 identical 1.5 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
32. 32.💡 3 identical bulbs are joined in parallel across a 12 V battery (ideal wires). How many volts does each bulb get? =
33. 33.🔐 Privacy for a smart device means controlling … (a) its battery size (b) who can see your data (c) how loud it beeps (d) its colour
34. 34.Which of these is a conductor? (a) a dry cork (b) a glass marble (c) a metal paper clip (d) a paper strip
35. 35.🔁 x = 3
    repeat 3 times { x = x × 2 }
    What is x at the end?
36. 36.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = I ÷ V (c) P = V × I (d) P = V + I
37. 37.Which drawing is the symbol for a motor? (a) a circle with a cross (b) many long-short pairs (c) a dot where wires meet (d) a circle with M inside
38. 38.🔁 x = 1
    repeat 2 times { x = x × 2 }
    What is x at the end?
39. 39.🔍 Which is the odd one out? (a) use old filament bulbs (b) close the fridge quickly (c) use LED lamps (d) switch off empty rooms
40. 40.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids