Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 280 · 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.🔗 Series or parallel circuit: “a break stops every bulb”? (a) parallel (b) series
2. 2.⚡ A home appliance on the 230 V mains takes 5 A. What is its power (in watts)?
3. 3.🔁 x = 1
   repeat 1 time { x = x × 2 }
   What is x at the end?
4. 4.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) gets bigger (b) stays the same (c) becomes zero (d) gets smaller
5. 5.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the if part (b) both parts (c) neither part (d) the else part
6. 6.🔍 Which is the odd one out? (a) build with an adult near (b) keep drinks far away (c) stay away from pylons (d) poke things in a socket
7. 7.True or false: “many paths for current” is true of a parallel circuit. (a) False (b) True
8. 8.Which of these is true of a series circuit? (a) bulbs share the voltage (b) one out, the rest glow (c) each gets the full volts (d) many paths for current
9. 9.🤖 Microcontroller or laptop: which one runs many apps at once? (a) microcontroller (b) laptop
10. 10.🔁 Is the circuit closed or open if a wire is cut? (a) closed (b) open
11. 11.🧮 Four equal 100 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
12. 12.💡 Why does an LED need a resistor in series? (a) to change its colour (b) to store charge (c) to limit the current (d) to make it brighter
13. 13.🔘 Which kind of switch stays where you flip it? (a) a reed switch (b) a push button (c) a toggle switch (d) a tilt switch
14. 14.🔍 Which is the odd one out? (a) an iron nail (b) a paper strip (c) a plastic ruler (d) a rubber band
15. 15.True or false: “a motion sensor signal” is the input. (a) True (b) False
16. 16.Which job is done by the power LED? (a) keeps the voltage steady (b) brings power and code (c) shows the board is on (d) runs the program
17. 17.💡 Does it save or waste electricity to set the AC to 24 °C? (a) wastes electricity (b) saves electricity
18. 18.Which of these mainly gives out heat? (a) a street light (b) an electric toy car (c) a water heater (d) a buzzer
19. 19.True or false: to fly a kite near wires is not safe. (a) False (b) True
20. 20.⚡ Power tells us … (a) the size of a cell (b) energy used each second (c) the length of a wire (d) the colour of light
21. 21.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) the shorter line (c) the longer line (d) neither line
22. 22.🔺 A current of 2 A flows through a 5 Ω resistor. What is the voltage across it (in volts)? =
23. 23.✏️ In a circuit diagram, which part is drawn as a small empty box? (a) ammeter (b) battery (c) resistor (d) voltmeter
24. 24.Which of these is a conductor? (a) a glass marble (b) a graphite rod (c) a cotton thread (d) a plastic ruler
25. 25.Which of these is a good habit? (a) share the Wi-Fi key (b) log out of shared phones (c) ignore update messages (d) keep factory passwords
26. 26.Which of these is an insulator? (a) a brass key (b) a graphite rod (c) a glass marble (d) a copper wire
27. 27.🔺 A current of 20 mA flows through a 400 Ω resistor. What is the voltage across it (in volts)? =
28. 28.🔘 Which kind of switch flips up or down? (a) a reed switch (b) a toggle switch (c) a slide switch (d) a push button
29. 29.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) False (b) True
30. 30.🔢 To get a sensor reading onto a phone, what comes right after “the cloud stores it”? (a) it is sent by Wi-Fi (b) the app shows it (c) the sensor measures (d) the board reads it
31. 31.True or false: to set the AC to 24 °C saves electricity. (a) False (b) True
32. 32.🔍 Which is the odd one out? (a) a soil moisture reading (b) count button presses (c) decide if soil is dry (d) compare with a limit
33. 33.🔍 Which is the odd one out? (a) a loudspeaker (b) a doorbell (c) a buzzer (d) a tube light
34. 34.⏱️ loop forever { LED ON; wait 650 ms; LED OFF; wait 1350 ms }
    How many times does the LED blink in 10 seconds?
35. 35.⏱️ A program says “wait 6500 ms”. How many seconds is that? =
36. 36.⚡ A 4.5 W device works on 1.5 V. What current does it take (in amperes)? =
37. 37.What does an LED do? (a) makes a beeping sound (b) boosts a small signal (c) glows using little power (d) limits the current
38. 38.True or false: a resistor smooths a wobbly supply. (a) True (b) False
39. 39.🤖 Microcontroller or laptop: which one uses very little power? (a) microcontroller (b) laptop
40. 40.🔦 A circuit has a new cell, a good bulb and a switch that is ON. One wire has come loose from the cell. Does the bulb glow? (a) No (b) Yes

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