Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 82 · 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.💡 Why is house wiring done in parallel? (a) so all go off together (b) to save copper only (c) to make bulbs dim (d) each gets full voltage
2. 2.🔁 x = 3
   repeat 3 times { x = x × 2 }
   What is x at the end?
3. 3.🔋 How many 1.5 V cells must be joined in series to give 10.5 V?
4. 4.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a brass key across the gap. Does the bulb glow? (a) Yes (b) No
5. 5.Which of these is measured in watts (W)? (a) the push of a cell (b) how much a part resists (c) energy used each second (d) resistance
6. 6.🔁 What must there be for a current to flow? (a) a plastic gap (b) a complete loop (c) a broken path (d) one loose end
7. 7.Which of these is a conductor? (a) a copper wire (b) a plastic ruler (c) a paper strip (d) a dry cork
8. 8.True or false: “one out, the rest glow” is true of a series circuit. (a) True (b) False
9. 9.True or false: “a soil moisture reading” is the input. (a) False (b) True
10. 10.⚡ Power tells us … (a) the size of a cell (b) the length of a wire (c) the colour of light (d) energy used each second
11. 11.🔺 An 8 V supply is joined across a 400 Ω resistor. What current flows (in milliamperes, mA)?
12. 12.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 65 Ω resistor? (a) violet-green-black (b) blue-green-brown (c) blue-green-black (d) green-blue-black
13. 13.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the else part (b) both parts (c) the if part (d) neither part
14. 14.⏱️ A program says “wait 5000 ms”. How many seconds is that? =
15. 15.🔺 A current of 0.1 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
16. 16.⚡ A device works on 24 V and takes 0.25 A. What is its power (in watts)? =
17. 17.Which job needs a temperature sensor? (a) warn of a gas leak (b) spot someone walking in (c) measure classroom noise (d) start a fan when hot
18. 18.🏠 Which is a smart-home example? (a) a candle in a jar (b) lights on from an app (c) a hand fan (d) a printed map
19. 19.🌐 What does IoT stand for? (a) Input of Tools (b) Internet of Talk (c) Inside of Toys (d) Internet of Things
20. 20.💡 Does it save or waste electricity to set the AC to 24 °C? (a) saves electricity (b) wastes electricity
21. 21.🔘 Which kind of switch slides side to side? (a) a slide switch (b) a push button (c) a reed switch (d) a toggle switch
22. 22.⏱️ loop forever { LED ON; wait 950 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 6 seconds?
23. 23.Which of these is a conductor? (a) a cotton thread (b) a brass key (c) a rubber band (d) a wooden stick
24. 24.🔺 A current of 0.1 A flows when 0.6 V is joined across a resistor. What is its resistance (in ohms)?
25. 25.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) diode (b) switch (c) junction (d) battery
26. 26.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
27. 27.What does a toggle switch do? (a) stays where you flip it (b) closes when tipped over (c) slides side to side (d) works only while pressed
28. 28.🔢 To plan an electronics project, what comes right after “list inputs and outputs”? (a) pick a problem to solve (b) draw the circuit diagram (c) build it with an adult (d) test it and fix it
29. 29.🔁 What do we call a circuit with a break in it? (a) an open circuit (b) a series circuit (c) a full circuit (d) a closed circuit
30. 30.True or false: “compare with a limit” is the process. (a) False (b) True
31. 31.🧾 A 500 W appliance runs for 6 hours. How many units (kWh) of electricity does it use? =
32. 32.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 7 LOW
    set pin 8 HIGH
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
33. 33.✏️ In a cell symbol, which line is the + terminal? (a) neither line (b) both lines (c) the longer line (d) the shorter line
34. 34.🔌 Is a woollen thread a conductor or an insulator? (a) a conductor (b) an insulator
35. 35.🔺 A 6 V supply is joined across a 150 Ω resistor. What current flows (in milliamperes, mA)?
36. 36.⏱️ loop forever { LED ON; wait 250 ms; LED OFF; wait 650 ms }
    How many milliseconds does one blink (ON + OFF) take?
37. 37.⚡ Which tiny particles drift along a metal wire to carry the current? (a) dust particles (b) electrons (c) water drops (d) photons
38. 38.🤖 Does a wind-up toy usually have a microcontroller inside? (a) Yes (b) No
39. 39.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) True (b) False
40. 40.🧩 Which component turns a fan or wheels? (a) transistor (b) motor (c) resistor (d) diode

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