Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 421 · 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.✏️ In a circuit diagram, which part is drawn as a circle with A inside? (a) switch (b) ammeter (c) resistor (d) motor
2. 2.Which of these is not an IoT device? (a) a Wi-Fi weather station (b) a smart energy meter (c) a paper calendar (d) a Wi-Fi doorbell camera
3. 3.Which job needs an LED? (a) show a status light (b) show the temperature (c) move water to plants (d) spin a robot’s wheels
4. 4.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) Yes (b) No
5. 5.True or false: a microcontroller runs one small program. (a) True (b) False
6. 6.📏 How many watts (W) is 1.2 kW?
7. 7.✏️ In a circuit diagram, which part is drawn as a straight line? (a) wire (b) cell (c) LED (d) voltmeter
8. 8.⚡ What does a loudspeaker mainly change electricity into? (a) movement (b) light (c) sound (d) heat
9. 9.True or false: to reuse one password is a risky habit. (a) False (b) True
10. 10.⚡ An 18 W device works on 6 V. What current does it take (in amperes)? =
11. 11.True or false: a fuse is a resistance knob. (a) False (b) True
12. 12.🔺 A current of 2.5 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
13. 13.Which of these saves electricity? (a) close the fridge quickly (b) iron one shirt at a time (c) leave the TV on standby (d) use old filament bulbs
14. 14.✏️ In a circuit diagram, wires are usually drawn as … (a) wavy lines (b) little stars (c) straight lines (d) dotted circles
15. 15.🧩 Which component glows using little power? (a) buzzer (b) LDR (c) LED (d) resistor
16. 16.🔁 repeat 3 times { repeat 5 times { beep } }
    How many beeps are there?
17. 17.What does a fuse do? (a) makes a beeping sound (b) blows if current is high (c) is a resistance knob (d) stores a little charge
18. 18.⚡ A home appliance on the 230 V mains takes 8 A. What is its power (in watts)?
19. 19.Which drawing is the symbol for a capacitor? (a) a circle with V inside (b) a plain rectangle (c) many long-short pairs (d) two equal parallel lines
20. 20.📏 Voltmeter or ammeter: which one is joined across a part? (a) ammeter (b) voltmeter
21. 21.⏱️ repeat 10 times { buzzer ON; wait 700 ms; buzzer OFF; wait 300 ms }
    How many milliseconds does this take in all?
22. 22.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) + (positive) (b) − (negative)
23. 23.🌈 A resistor has the colour bands yellow, orange, red. What is its value in kilo-ohms (kΩ)? =
24. 24.True or false: to leave the TV on standby saves electricity. (a) True (b) False
25. 25.Which of these usually has a microcontroller inside? (a) a plain wall switch (b) a candle (c) a spinning top (d) a digital alarm clock
26. 26.🔘 Which kind of switch springs back when let go? (a) a push button (b) a reed switch (c) a toggle switch (d) a slide switch
27. 27.Which of these is measured in volts (V)? (a) current (b) the push of a cell (c) power (d) how much a part resists
28. 28.🔺 A current of 0.2 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
29. 29.🌈 A resistor has the colour bands white, yellow, yellow. What is its value in kilo-ohms (kΩ)? =
30. 30.💡 Why does an LED need a resistor in series? (a) to store charge (b) to make it brighter (c) to change its colour (d) to limit the current
31. 31.🔺 A current of 25 mA flows through a 120 Ω resistor. What is the voltage across it (in volts)? =
32. 32.True or false: to dry your hands first is not safe. (a) False (b) True
33. 33.Which job needs a buzzer? (a) show a status light (b) move water to plants (c) beep an alarm (d) show the temperature
34. 34.💡 An LED is joined to a 9 V battery through a 1000 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) lights up (b) may burn out (c) does not light
35. 35.🔦 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 wooden stick. Does the bulb glow? (a) No (b) Yes
36. 36.🔘 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 ON, B is ON and C is ON. Does the bulb glow? (a) Yes (b) No
37. 37.📏 Voltmeter or ammeter: which one is joined in series? (a) voltmeter (b) ammeter
38. 38.🔋 3 identical 2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
39. 39.🔌 Is a ceramic cup a conductor or an insulator? (a) a conductor (b) an insulator
40. 40.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 26) { show “Warm” } else { show “Cool” }
    The temperature is 24 °C. What is shown? (a) Hot (b) Warm (c) Cool

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