Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 79 · 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.🤖 “if (A AND B)” is true when … (a) only B is true (b) both are false (c) both A and B are true (d) only A is true
2. 2.Which of these uses electricity? (a) a water pump (b) a generator (c) a wind turbine (d) a bicycle dynamo
3. 3.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
4. 4.True or false: a buzzer beeps for an alarm. (a) True (b) False
5. 5.Which of these is the output? (a) a soil moisture reading (b) a temperature reading (c) the pump turns on (d) compare with a limit
6. 6.🔦 A circuit has a used-up (dead) cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a rubber band. Does the bulb glow? (a) No (b) Yes
7. 7.🔌 Is an LED an input or an output for a microcontroller? (a) output (b) input
8. 8.🔋 4 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
9. 9.True or false: a rubber band is an insulator. (a) False (b) True
10. 10.What does a tilt switch do? (a) springs back when let go (b) closes when tipped over (c) slides side to side (d) stays where you flip it
11. 11.True or false: to close the fridge quickly saves electricity. (a) False (b) True
12. 12.🧩 A capacitor in a circuit can … (a) make light (b) spin a wheel (c) measure heat (d) store charge briefly
13. 13.⚡ Power tells us … (a) the size of a cell (b) the colour of light (c) energy used each second (d) the length of a wire
14. 14.Which job needs a rain sensor? (a) water a dry plant (b) warn of a gas leak (c) spot someone walking in (d) close a window in rain
15. 15.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets smaller (b) stays the same (c) gets bigger (d) becomes zero
16. 16.⏱️ A program says “wait 9500 ms”. How many seconds is that? =
17. 17.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
18. 18.🔺 An 8.25 V supply is joined across a 330 Ω resistor. What current flows (in milliamperes, mA)?
19. 19.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 560 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
20. 20.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. A gap in one wire is bridged by a rubber eraser. Does the bulb glow? (a) No (b) Yes
21. 21.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
22. 22.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 LOW
    set pin 7 LOW
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
23. 23.Which of these means the circuit is closed? (a) a wire has come loose (b) the switch is ON (c) the switch is OFF (d) a wire is cut
24. 24.Which job needs a display? (a) show the temperature (b) turn to an exact angle (c) spin a robot’s wheels (d) show a status light
25. 25.💡 3 identical bulbs are in parallel and each bulb has its own switch on its path. 1 of the switches is OFF and the rest are ON. How many bulbs glow?
26. 26.⏱️ A program says “wait 1750 ms”. How many seconds is that? =
27. 27.Which of these means the circuit is open? (a) a wire has come loose (b) all wires are joined (c) the switch is ON (d) the loop is complete
28. 28.✏️ In a circuit diagram, which part is drawn as two or more cell symbols? (a) bulb (b) battery (c) resistor (d) cell
29. 29.✏️ In a circuit diagram, which part is drawn as a dot where wires meet? (a) battery (b) LED (c) wire (d) junction
30. 30.📏 In the water-pipe picture of a circuit, voltage is like … (a) the water tank lid (b) the water pressure (c) the pipe colour (d) the tap handle
31. 31.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 410 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON
32. 32.Which of these is an IoT device? (a) a battery torch (b) a plain wall switch (c) a plain table fan (d) a Wi-Fi weather station
33. 33.Which job needs a pump? (a) turn to an exact angle (b) spin a robot’s wheels (c) show a status light (d) move water to plants
34. 34.🔺 A current of 20 mA flows through a 220 Ω resistor. What is the voltage across it (in volts)? =
35. 35.Which of these is an IoT device? (a) a plain table fan (b) a wind-up clock (c) a smart energy meter (d) a paper calendar
36. 36.Which job needs a light sensor? (a) water a dry plant (b) close a window in rain (c) switch on lamps at dusk (d) keep an incubator warm
37. 37.💡 What happens if an LED is put in backwards? (a) it makes a sound (b) it changes colour (c) it lights brighter (d) it does not light
38. 38.📏 Voltmeter or ammeter: which one measures current? (a) ammeter (b) voltmeter
39. 39.Which job is done by the USB port? (a) brings power and code (b) keeps the voltage steady (c) shows the board is on (d) restarts the program
40. 40.⚠️ Who should be with you when you build a circuit? (a) nobody (b) a younger child (c) a trusted adult (d) a stranger online

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