Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 551 · 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.📶 On a 5 V board, a pin set HIGH gives about … (a) 5 V (b) 230 V (c) 50 V (d) 0 V
2. 2.🔍 For a microcontroller, is a sensor an input or an output? (a) an output (b) a power source (c) an input (d) a fuse
3. 3.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) − (negative) (b) + (positive)
4. 4.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
5. 5.⚡ A home appliance on the 230 V mains takes 10 A. What is its power (in watts)?
6. 6.🔍 Which is the odd one out? (a) a buzzer (b) a mixer grinder (c) an electric drill (d) a ceiling fan
7. 7.Which of these is a risky habit? (a) set a strong password (b) read app permissions (c) set up with a parent (d) keep factory passwords
8. 8.True or false: on an LED, the longer leg is the cathode (−). (a) False (b) True
9. 9.🌈 In the resistor colour code, which number does orange stand for?
10. 10.True or false: on a cell, “the longer symbol line” means the − (negative) end. (a) False (b) True
11. 11.💡 Does it save or waste electricity to close the fridge quickly? (a) wastes electricity (b) saves electricity
12. 12.⏱️ loop forever { LED ON; wait 900 ms; LED OFF; wait 1100 ms }
    How many times does the LED blink in 6 seconds?
13. 13.🔘 A bulb and a cell are joined through 6 switches one after another in a single loop (series). What is the smallest number of switches that must be ON to light the bulb?
14. 14.🔌 Why are electric wires covered in plastic? (a) to make them heavy (b) plastic is a conductor (c) plastic is an insulator (d) plastic makes current
15. 15.Which of these is a risky habit? (a) share camera links (b) set up with a parent (c) change default passwords (d) install software updates
16. 16.🔗 Series or parallel circuit: “own switch for each bulb”? (a) series (b) parallel
17. 17.True or false: if the bulb is unscrewed, the circuit is open and no current flows. (a) False (b) True
18. 18.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) straight lines (c) dotted circles (d) wavy lines
19. 19.🧩 Which component has coloured bands? (a) motor (b) fuse (c) resistor (d) potentiometer
20. 20.True or false: “each gets the full volts” is true of a parallel circuit. (a) False (b) True
21. 21.🔋 Does a television give electricity or use electricity? (a) uses electricity (b) gives electricity
22. 22.🔌 Is a woollen thread a conductor or an insulator? (a) an insulator (b) a conductor
23. 23.🧩 A capacitor in a circuit can … (a) spin a wheel (b) store charge briefly (c) measure heat (d) make light
24. 24.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) False (b) True
25. 25.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 130 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
26. 26.🔘 Two switches are in parallel (side by side). When does the bulb glow? (a) when either is ON (b) only when both are ON (c) only when both are OFF (d) never
27. 27.Which of these is an insulator? (a) a steel coin (b) a rubber band (c) a copper wire (d) a graphite rod
28. 28.True or false: to touch a fallen wire is not safe. (a) False (b) True
29. 29.🔍 Which is the odd one out? (a) use a cable with cuts (b) fly kites in open fields (c) fly a kite near wires (d) touch a fallen wire
30. 30.💡 Old festival light strings went fully dark when one bulb failed. How were they joined? (a) not joined (b) in series (c) in parallel (d) by Wi-Fi
31. 31.🧮 Resistors of 68 Ω and 330 Ω are joined in series. What is the total resistance (in ohms)?
32. 32.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 120 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
33. 33.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a woollen thread across the gap. Does the bulb glow? (a) No (b) Yes
34. 34.What does a transistor do? (a) senses how bright it is (b) smooths a wobbly supply (c) boosts a small signal (d) turns a fan or wheels
35. 35.💡 An LED is joined to a 6 V battery with no resistor; the leg next to the flat edge of its rim goes to the − side. What happens? (a) lights up (b) does not light (c) may burn out
36. 36.True or false: on an LED, the round-side leg is the anode (+). (a) False (b) True
37. 37.🤖 if (light < 400 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 50 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
38. 38.Which of these is an insulator? (a) a paper strip (b) a graphite rod (c) a copper wire (d) a steel spoon
39. 39.⚠️ Is it safe to open a phone charger? (a) safe (b) not safe
40. 40.🔺 A 1.2 V supply is joined across a 120 Ω resistor. What current flows (in milliamperes, mA)?

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