Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 869 · 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 actuator would you use to show a status light? (a) a display (b) a pump (c) an LED (d) a buzzer
2. 2.🤖 if (sound > 60) { red LED ON } else { green LED ON }
   The sound sensor reads 45. What happens? (a) red LED ON (b) green LED ON
3. 3.🔁 Is the circuit closed or open if all wires are joined? (a) open (b) closed
4. 4.🔢 To run one loop of a plant-watering program, which comes first: “compare with the limit” or “read the soil sensor”? (a) compare with the limit (b) read the soil sensor
5. 5.🤖 Does a hand pump usually have a microcontroller inside? (a) Yes (b) No
6. 6.🔍 Which is the odd one out? (a) a graphite rod (b) a steel coin (c) a copper wire (d) a wooden stick
7. 7.🔺 In the V-I-R triangle, how do we find R? (a) R = V × I (b) R = I ÷ V (c) R = V + I (d) R = V ÷ I
8. 8.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) neither line (c) the longer line (d) the shorter line
9. 9.Which of these wastes electricity? (a) set the AC to 24 °C (b) use old filament bulbs (c) use LED lamps (d) unplug idle chargers
10. 10.True or false: a water heater mainly gives out light. (a) False (b) True
11. 11.💡 3 identical bulbs are joined in series with a 9 V battery (ideal wires). How many volts does each bulb get? =
12. 12.🔘 Two switches are in series. When does the bulb glow? (a) never (b) when both are OFF (c) when both are ON (d) when either is ON
13. 13.True or false: two equal parallel lines is the symbol for a capacitor. (a) True (b) False
14. 14.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
15. 15.🔺 A current of 20 mA flows when 10 V is joined across a resistor. What is its resistance (in ohms)?
16. 16.Which drawing is the symbol for a cell? (a) one tall, one short bar (b) two or more cell symbols (c) a circle with a cross (d) a circle with V inside
17. 17.True or false: “one bulb out, all go out” is true of a series circuit. (a) False (b) True
18. 18.🌈 A resistor has the colour bands brown, yellow, black. What is its value (in ohms)?
19. 19.Which of these is true of a parallel circuit? (a) bulbs share the voltage (b) one bulb out, all go out (c) a single current path (d) one out, the rest glow
20. 20.True or false: to build with an adult near is not safe. (a) True (b) False
21. 21.True or false: “many values in a range” is an analog signal. (a) True (b) False
22. 22.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
23. 23.⚡ A 2.25 W device works on 1.5 V. What current does it take (in amperes)? =
24. 24.Which job needs a motion sensor? (a) start a fan when hot (b) keep an incubator warm (c) switch on lamps at dusk (d) spot someone walking in
25. 25.📶 On a 5 V board, a pin set HIGH gives about … (a) 0 V (b) 50 V (c) 230 V (d) 5 V
26. 26.⏱️ How many milliseconds is a wait of 4.3 seconds?
27. 27.🏠 Which is a smart-home example? (a) lights on from an app (b) a hand fan (c) a printed map (d) a candle in a jar
28. 28.🔋 4 identical 2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
29. 29.Which of these is measured in ohms (Ω)? (a) the flow of charge (b) energy used each second (c) power (d) resistance
30. 30.🔍 Which is the odd one out? (a) count button presses (b) a motion sensor signal (c) compare with a limit (d) check if temp > 30
31. 31.🔍 Which is the odd one out? (a) turn off unused gadgets (b) ignore update messages (c) cover unused cameras (d) set a strong password
32. 32.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) by Wi-Fi (b) in series (c) in parallel (d) not joined
33. 33.Which of these is a conductor? (a) a cotton thread (b) a plastic straw (c) a plastic ruler (d) a safety pin
34. 34.Which of these is safe? (a) touch a fallen wire (b) use mains for a project (c) climb an electric pole (d) stay away from pylons
35. 35.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) parallel (b) series
36. 36.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) stay the same (c) bigger (d) smaller
37. 37.Which job needs a temperature sensor? (a) start a fan when hot (b) close a window in rain (c) spot someone walking in (d) measure classroom noise
38. 38.Which drawing is the symbol for a junction? (a) a straight line (b) a line lifted at a gap (c) a small empty box (d) a dot where wires meet
39. 39.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 150 ms }
    How many times does the LED blink in 9 seconds?
40. 40.Which of these means the circuit is closed? (a) a wire has come loose (b) the switch is ON (c) the bulb is unscrewed (d) the switch is OFF

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