Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 477 · 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 cell, does “the shorter symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
2. 2.Which of these is measured in watts (W)? (a) energy used each second (b) voltage (c) the flow of charge (d) current
3. 3.🧾 A 100 W appliance runs for 5 hours. How many units (kWh) of electricity does it use? =
4. 4.True or false: a resistor turns a fan or wheels. (a) True (b) False
5. 5.💡 What does LED stand for? (a) low energy device (b) large electric dial (c) light energy dial (d) light-emitting diode
6. 6.Which of these is not safe? (a) touch a switch when wet (b) use small battery cells (c) build with an adult near (d) fly kites in open fields
7. 7.Which job needs a sound sensor? (a) water a dry plant (b) switch on with a clap (c) warn of a gas leak (d) open blinds at sunrise
8. 8.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) becomes zero (b) stays the same (c) gets bigger (d) gets smaller
9. 9.🌐 A soil sensor sends a reading to an app every 5 minutes. How many readings arrive in 2 hours?
10. 10.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a metal paper clip across the gap. Does the bulb glow? (a) No (b) Yes
11. 11.Which of these usually has a microcontroller inside? (a) a candle (b) a wind-up toy (c) a microwave oven (d) a bicycle bell
12. 12.True or false: if the loop is complete, the circuit is open and no current flows. (a) True (b) False
13. 13.⚡ What does a doorbell mainly change electricity into? (a) movement (b) heat (c) light (d) sound
14. 14.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
15. 15.⚡ Which formula gives electric power? (a) P = V + I (b) P = V × I (c) P = V ÷ I (d) P = I ÷ V
16. 16.🔍 Which is the odd one out? (a) leave the TV on standby (b) run fans in empty rooms (c) set the AC to 24 °C (d) iron one shirt at a time
17. 17.💡 3 identical bulbs are joined in parallel across a 1.5 V battery (ideal wires). How many volts does each bulb get? =
18. 18.📏 Voltmeter or ammeter: which one is joined across a part? (a) voltmeter (b) ammeter
19. 19.True or false: many long-short pairs is the symbol for a battery. (a) True (b) False
20. 20.🔋 Cells joined + to − in a row (series) give … (a) the same voltage (b) a smaller voltage (c) no voltage (d) a bigger voltage
21. 21.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) share it with friends (b) post it online (c) ask a parent first (d) type it all in
22. 22.True or false: “a break stops every bulb” is true of a series circuit. (a) False (b) True
23. 23.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
24. 24.🔁 count = 0
    repeat 2 times { count = count + 6 }
    What is count at the end?
25. 25.True or false: “many values in a range” is a digital signal. (a) True (b) False
26. 26.What does a transistor do? (a) stores a little charge (b) boosts a small signal (c) beeps for an alarm (d) lets current go one way
27. 27.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a copper wire across the gap. Does the bulb glow? (a) No (b) Yes
28. 28.True or false: to set the AC to 24 °C wastes electricity. (a) False (b) True
29. 29.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) tell it your passwords (b) let strangers use it (c) put it in the bathroom (d) mute it when not in use
30. 30.Which of these is safe? (a) poke things in a socket (b) fly kites in open fields (c) open a phone charger (d) touch a switch when wet
31. 31.🔦 A circuit has a new cell, a bulb with a broken filament and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a ceramic cup. Does the bulb glow? (a) No (b) Yes
32. 32.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is OFF, B is ON and C is OFF. Does the bulb glow? (a) No (b) Yes
33. 33.🔗 Series or parallel circuit: “own switch for each bulb”? (a) parallel (b) series
34. 34.⚡ A device works on 3 V and takes 0.2 A. What is its power (in watts)? =
35. 35.🔋 How many volts does one ordinary torch cell give? (a) 1.5 V (b) 230 V (c) 15 V (d) 0.5 V
36. 36.🤖 if (light < 200 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 530 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
37. 37.🔋 Does a solar panel give electricity or use electricity? (a) uses electricity (b) gives electricity
38. 38.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 360 Ω resistor? (a) blue-orange-brown (b) orange-blue-red (c) orange-blue-black (d) orange-blue-brown
39. 39.True or false: a capacitor stores a little charge. (a) True (b) False
40. 40.⚡ A solar panel changes which kind of energy into electricity? (a) light energy (b) sound energy (c) chemical energy (d) wind energy

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