Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 570 · 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 is the odd one out? (a) fly a kite near wires (b) use small battery cells (c) fly kites in open fields (d) stay away from pylons
2. 2.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) parallel (b) series
3. 3.Which of these is a risky habit? (a) ignore update messages (b) change default passwords (c) install software updates (d) read app permissions
4. 4.Which drawing is the symbol for a battery? (a) a circle with V inside (b) a straight line (c) two or more cell symbols (d) a circle with A inside
5. 5.🗺️ In an input → process → output plan, is “a button press” the input, the process or the output? (a) process (b) input (c) output
6. 6.🔺 A current of 0.1 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
7. 7.🔁 repeat 3 times { repeat 3 times { beep } }
   How many beeps are there?
8. 8.🔍 Which is the odd one out? (a) compare with a limit (b) check if temp > 30 (c) decide if soil is dry (d) the pump turns on
9. 9.Which of these is not safe? (a) fly kites in open fields (b) touch a switch when wet (c) stay away from pylons (d) dry your hands first
10. 10.Which drawing is the symbol for a switch? (a) a plain rectangle (b) a long and a short line (c) a line lifted at a gap (d) one tall, one short bar
11. 11.🔺 A 4 V supply is joined across a 4 Ω resistor. What current flows (in amperes)? =
12. 12.🔦 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
13. 13.🔋 Identical cells side by side (in parallel) give … (a) double the voltage (b) the same voltage (c) half the voltage (d) no voltage
14. 14.🔍 Which is the odd one out? (a) a steel spoon (b) a rubber eraser (c) a plastic ruler (d) a paper strip
15. 15.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) − (negative) (b) + (positive)
16. 16.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they get dimmer (b) they explode (c) they keep glowing (d) they all go out
17. 17.💡 A red LED (it uses 2 V) is joined with a 150 Ω resistor to a 2.75 V supply. What current flows (in mA)?
18. 18.🤖 if (distance < 10) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 9 cm. What happens? (a) buzzer beeps (b) buzzer is silent
19. 19.🧩 Which component smooths a wobbly supply? (a) motor (b) resistor (c) thermistor (d) capacitor
20. 20.True or false: a plain rectangle is the symbol for a junction. (a) True (b) False
21. 21.⚡ Which formula gives electric power? (a) P = V ÷ I (b) P = V + I (c) P = I ÷ V (d) P = V × I
22. 22.What does a motor do? (a) stores a little charge (b) turns a fan or wheels (c) is a resistance knob (d) boosts a small signal
23. 23.💡 A blue LED uses 3 V and should get 10 mA. It runs from a 5 V supply. What resistor (in ohms) is needed in series?
24. 24.Which of these is measured in ohms (Ω)? (a) power (b) voltage (c) resistance (d) the flow of charge
25. 25.🧾 A 100 W appliance runs for 4 hours. How many units (kWh) of electricity does it use? =
26. 26.What does the microcontroller do? (a) carries the data (b) measures the real world (c) reads values, decides (d) acts on a command
27. 27.✏️ In a circuit diagram, which part is drawn as a circle with a cross? (a) wire (b) battery (c) resistor (d) bulb
28. 28.💡 Does it save or waste electricity to leave the TV on standby? (a) saves electricity (b) wastes electricity
29. 29.📏 In the water-pipe picture of a circuit, current is like … (a) the pipe colour (b) the water pressure (c) the flow of water (d) a narrow pipe
30. 30.True or false: a digital thermometer has no microcontroller inside. (a) True (b) False
31. 31.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 590 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
32. 32.Which job is done by the pins? (a) connect sensors and LEDs (b) restarts the program (c) keeps the voltage steady (d) brings power and code
33. 33.🌐 Is a Wi-Fi doorbell camera an IoT device? (a) an IoT device (b) not an IoT device
34. 34.True or false: if a cell is taken out, the circuit is open and no current flows. (a) True (b) False
35. 35.📏 Voltmeter or ammeter: which one is joined across a part? (a) ammeter (b) voltmeter
36. 36.🔺 A current of 40 mA flows through a 470 Ω resistor. What is the voltage across it (in volts)? =
37. 37.💡 A red LED (it uses 2 V) is joined with a 150 Ω resistor to a 3.5 V supply. What current flows (in mA)?
38. 38.🔗 Series or parallel circuit: “one out, the rest glow”? (a) series (b) parallel
39. 39.⚡ Power tells us … (a) the colour of light (b) the length of a wire (c) the size of a cell (d) energy used each second
40. 40.🔍 Which is the odd one out? (a) a buzzer beeps (b) a soil moisture reading (c) a temperature reading (d) a motion sensor signal

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