Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 397 · 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 a loudspeaker mainly change electricity into? (a) heat (b) light (c) movement (d) sound
2. 2.True or false: an iron nail is a conductor. (a) True (b) False
3. 3.Which of these usually has a microcontroller inside? (a) a plain wall switch (b) a spinning top (c) a wind-up toy (d) a microwave oven
4. 4.Which of these is a risky habit? (a) read app permissions (b) accept every permission (c) cover unused cameras (d) set up with a parent
5. 5.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) neither line (c) the shorter line (d) both lines
6. 6.💡 Why is house wiring done in parallel? (a) each gets full voltage (b) so all go off together (c) to make bulbs dim (d) to save copper only
7. 7.Which job needs a pump? (a) move water to plants (b) beep an alarm (c) show the temperature (d) show a status light
8. 8.🔺 A current of 40 mA flows through a 250 Ω resistor. What is the voltage across it (in volts)? =
9. 9.🔺 A current of 0.5 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
10. 10.True or false: the ammeter is joined in series. (a) False (b) True
11. 11.🔺 A current of 0.1 A flows when 0.8 V is joined across a resistor. What is its resistance (in ohms)?
12. 12.⏱️ How many milliseconds are in 1 second? (a) 100 (b) 60 (c) 1000 (d) 10
13. 13.Which drawing is the symbol for a resistor? (a) a circle with a cross (b) triangle against a bar (c) a plain rectangle (d) two equal parallel lines
14. 14.🔍 Which is the odd one out? (a) a small display (b) a push button (c) a buzzer (d) a servo motor
15. 15.True or false: a circle with an X in it is the symbol for a bulb. (a) True (b) False
16. 16.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
17. 17.Which job is done by the USB port? (a) shows the board is on (b) connect sensors and LEDs (c) keeps the voltage steady (d) brings power and code
18. 18.🔺 A current of 0.2 A flows through a 15 Ω resistor. What is the voltage across it (in volts)? =
19. 19.🔍 Which is the odd one out? (a) keep drinks far away (b) throw cells in a fire (c) touch a fallen wire (d) poke things in a socket
20. 20.💡 2 identical bulbs are joined in series with a 6 V battery (ideal wires). How many volts does each bulb get? =
21. 21.Which of these is the process? (a) a light level reading (b) compare with a limit (c) a temperature reading (d) a soil moisture reading
22. 22.🧩 A capacitor in a circuit can … (a) spin a wheel (b) measure heat (c) make light (d) store charge briefly
23. 23.True or false: to water a dry plant, use a light sensor. (a) True (b) False
24. 24.Which of these is measured in volts (V)? (a) energy used each second (b) current (c) the flow of charge (d) voltage
25. 25.⚡ Which formula gives electric power? (a) P = V × I (b) P = I ÷ V (c) P = V + I (d) P = V ÷ I
26. 26.🔁 Is the circuit closed or open if all wires are joined? (a) open (b) closed
27. 27.Which of these saves electricity? (a) leave the TV on standby (b) unplug idle chargers (c) leave fridge door open (d) iron one shirt at a time
28. 28.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
29. 29.📏 Voltmeter or ammeter: which one is joined across a part? (a) ammeter (b) voltmeter
30. 30.⚡ A 3 W device works on 12 V. What current does it take (in amperes)? =
31. 31.True or false: an LED glows using little power. (a) True (b) False
32. 32.🔘 A cell, a bulb and switches A and B are joined one after another in a single loop (series). A is OFF and B is ON. Does the bulb glow? (a) No (b) Yes
33. 33.🔁 Is the circuit closed or open if the switch is OFF? (a) closed (b) open
34. 34.🗺️ Before building a project, what should you write down first? (a) nothing at all (b) the box colour (c) the final price (d) inputs and outputs
35. 35.🔍 Which is the odd one out? (a) a plain wall switch (b) a Wi-Fi doorbell camera (c) a paper calendar (d) a plain table fan
36. 36.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
37. 37.💡 Does it save or waste electricity to use daylight to read? (a) wastes electricity (b) saves electricity
38. 38.🔁 count = 10
    repeat 4 times { count = count + 7 }
    What is count at the end?
39. 39.💡 4 identical bulbs are in parallel and each one takes 1.5 A. What total current (in amperes) comes from the battery? =
40. 40.📏 How many kilowatts (kW) is 3300 W? =

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