Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 576 · 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.What does an LED do? (a) beeps for an alarm (b) turns a fan or wheels (c) glows using little power (d) senses how bright it is
2. 2.True or false: aluminium foil is a conductor. (a) False (b) True
3. 3.⏱️ How many milliseconds is a wait of 1.1 seconds?
4. 4.What does a potentiometer do? (a) is a resistance knob (b) makes a beeping sound (c) senses how bright it is (d) glows using little power
5. 5.🔍 Which is the odd one out? (a) touch a switch when wet (b) stop if a part gets hot (c) use small battery cells (d) fly kites in open fields
6. 6.🌈 A resistor has the colour bands yellow, green, red. What is its value in kilo-ohms (kΩ)? =
7. 7.What does a push button do? (a) flips up or down (b) closes when tipped over (c) slides side to side (d) works only while pressed
8. 8.Which drawing is the symbol for a bulb? (a) triangle, bar and arrows (b) many long-short pairs (c) a circle with a cross (d) a long and a short line
9. 9.Which job needs a distance sensor? (a) spot someone walking in (b) make a parking alarm (c) switch on lamps at dusk (d) keep an incubator warm
10. 10.🤖 “if (A AND B)” is true when … (a) only B is true (b) only A is true (c) both are false (d) both A and B are true
11. 11.🌈 Which band is read first on a resistor? (a) any band (b) the widest gap (c) the one nearest an end (d) the gold band
12. 12.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a rubber band across the gap. Does the bulb glow? (a) No (b) Yes
13. 13.🧾 Which lamp gives the same light for the least power? (a) a filament bulb (b) a candle (c) an LED lamp (d) an oil lamp
14. 14.Which of these is the process? (a) the fan starts (b) decide if soil is dry (c) an alert on the phone (d) a button press
15. 15.🔋 What should you do with used-up cells? (a) bury them in soil (b) give them for recycling (c) throw them in a fire (d) cut them open
16. 16.🔺 A current of 50 mA flows through a 330 Ω resistor. What is the voltage across it (in volts)? =
17. 17.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 600 ms }
    How many milliseconds does one blink (ON + OFF) take?
18. 18.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) False (b) True
19. 19.🔍 Which is the odd one out? (a) an iron nail (b) a graphite rod (c) a woollen thread (d) aluminium foil
20. 20.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 7 HIGH
    set pin 7 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
21. 21.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
22. 22.🧩 Which component smooths a wobbly supply? (a) resistor (b) LDR (c) capacitor (d) fuse
23. 23.🔍 Which is the odd one out? (a) iron one shirt at a time (b) leave fridge door open (c) run fans in empty rooms (d) use LED lamps
24. 24.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 100 ms }
    How many milliseconds does one blink (ON + OFF) take?
25. 25.True or false: a smart watch has no microcontroller inside. (a) False (b) True
26. 26.🔍 Which sensor would you use to start a fan when hot? (a) a gas sensor (b) a motion sensor (c) a distance sensor (d) a temperature sensor
27. 27.🔍 Which is the odd one out? (a) use small battery cells (b) dry your hands first (c) stay away from pylons (d) poke things in a socket
28. 28.⚠️ What protects home wiring by melting or tripping when too much current flows? (a) a fuse or MCB (b) a plug top (c) a long wire (d) a bulb
29. 29.Which of these is not an IoT device? (a) a Wi-Fi weather station (b) a Wi-Fi doorbell camera (c) an app-controlled bulb (d) a plain table fan
30. 30.🗺️ In an input → process → output plan, is “the pump turns on” the input, the process or the output? (a) process (b) output (c) input
31. 31.True or false: on a cell, “the flat end” means the + (positive) end. (a) True (b) False
32. 32.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 8 HIGH
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
33. 33.Which of these means the circuit is open? (a) the switch is ON (b) all wires are joined (c) a wire is cut (d) the loop is complete
34. 34.Which of these means the circuit is closed? (a) a wire has come loose (b) the switch is OFF (c) all wires are joined (d) a cell is taken out
35. 35.Which of these is the output? (a) a light level reading (b) check if temp > 30 (c) the fan starts (d) decide if soil is dry
36. 36.🔁 total = 0
    for i = 1 to 6 { total = total + i }
    What is total at the end?
37. 37.What does a motor do? (a) blows if current is high (b) has coloured bands (c) is a resistance knob (d) makes things spin
38. 38.⚙️ Which actuator would you use to move water to plants? (a) an LED (b) a display (c) a pump (d) a motor
39. 39.💡 A battery lights 5 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same
40. 40.True or false: “a break stops every bulb” is true of a parallel circuit. (a) True (b) False

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