Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 65 · 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.True or false: to fly kites in open fields is safe. (a) True (b) False
2. 2.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) bulb (b) junction (c) battery (d) wire
3. 3.True or false: “many paths for current” is true of a series circuit. (a) True (b) False
4. 4.🧮 A 20 Ω resistor is joined in series with two equal 330 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
5. 5.Which of these is safe? (a) touch a fallen wire (b) climb an electric pole (c) throw cells in a fire (d) dry your hands first
6. 6.Which job needs a motion sensor? (a) spot someone walking in (b) switch on lamps at dusk (c) measure classroom noise (d) open blinds at sunrise
7. 7.What does a fuse do? (a) turns a fan or wheels (b) senses how hot it is (c) senses how bright it is (d) blows if current is high
8. 8.🔍 Which is the odd one out? (a) use mains for a project (b) fly a kite near wires (c) take cells out after use (d) climb an electric pole
9. 9.True or false: on an LED, the longer leg is the anode (+). (a) True (b) False
10. 10.True or false: a resistor senses how bright it is. (a) True (b) False
11. 11.📶 Digital or analog: HIGH or LOW only? (a) analog (b) digital
12. 12.⚡ 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
13. 13.Which of these is a good habit? (a) keep factory passwords (b) share camera links (c) accept every permission (d) set up with a parent
14. 14.Which of these is true of a parallel circuit? (a) bulbs share the voltage (b) used in house wiring (c) a single current path (d) a break stops every bulb
15. 15.🔺 A current of 20 mA flows when 3 V is joined across a resistor. What is its resistance (in ohms)?
16. 16.Which of these usually has a microcontroller inside? (a) a microwave oven (b) a candle (c) a wind-up toy (d) a spinning top
17. 17.💡 4 identical bulbs are joined in series with a 6 V battery (ideal wires). How many volts does each bulb get? =
18. 18.True or false: “the pump turns on” is the output. (a) True (b) False
19. 19.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 watt (c) 1 kilowatt-hour (kWh) (d) 1 volt
20. 20.🔦 A circuit has a new 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 woollen thread. Does the bulb glow? (a) No (b) Yes
21. 21.🔁 repeat 3 times { repeat 6 times { beep } }
    How many beeps are there?
22. 22.🔍 Which is the odd one out? (a) a night lamp (b) a traffic signal (c) a torch (d) a siren
23. 23.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a wooden stick across the gap. Does the bulb glow? (a) No (b) Yes
24. 24.💡 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?
25. 25.⚠️ Is it safe to open a phone charger? (a) not safe (b) safe
26. 26.⚙️ Which actuator would you use to show a status light? (a) a display (b) a pump (c) a motor (d) an LED
27. 27.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 520 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
28. 28.🤖 if (temperature > 35) { show “Hot” } else if (temperature > 22) { show “Warm” } else { show “Cool” }
    The temperature is 22 °C. What is shown? (a) Cool (b) Hot (c) Warm
29. 29.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a ceramic cup across the gap. Does the bulb glow? (a) No (b) Yes
30. 30.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
31. 31.True or false: to switch on with a clap, use a sound sensor. (a) True (b) False
32. 32.🔁 count = 6
    repeat 10 times { count = count + 5 }
    What is count at the end?
33. 33.True or false: on a cell, “usually the red wire” means the − (negative) end. (a) True (b) False
34. 34.🔺 In the V-I-R triangle, how do we find V? (a) V = I × R (b) V = I ÷ R (c) V = I + R (d) V = R ÷ I
35. 35.🔺 A current of 20 mA flows when 4 V is joined across a resistor. What is its resistance (in ohms)?
36. 36.🧩 Which component limits the current? (a) potentiometer (b) LDR (c) resistor (d) capacitor
37. 37.True or false: if a wire has come loose, the circuit is closed and current flows. (a) True (b) False
38. 38.🔺 In the V-I-R triangle, how do we find I? (a) I = V × R (b) I = R ÷ V (c) I = V ÷ R (d) I = V + R
39. 39.📏 Which unit measures energy used each second? (a) ohm (Ω) (b) watt (W) (c) ampere (A) (d) volt (V)
40. 40.True or false: “bulbs share the voltage” is true of a series circuit. (a) False (b) True

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