Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 590 · 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 “if (temp > 30)”, what runs when temp is exactly 30? (a) the if part (b) neither part (c) both parts (d) the else part
2. 2.🔋 Does a generator give electricity or use electricity? (a) gives electricity (b) uses electricity
3. 3.⏱️ A program says “wait 3750 ms”. How many seconds is that? =
4. 4.Which of these is not safe? (a) fly kites in open fields (b) stay away from pylons (c) stop if a part gets hot (d) throw cells in a fire
5. 5.🔁 repeat 3 times { repeat 3 times { beep } }
   How many beeps are there?
6. 6.🔺 A current of 10 mA flows when 2.2 V is joined across a resistor. What is its resistance (in ohms)?
7. 7.Which of these is an output? (a) a push button (b) a motion sensor (c) a water pump (d) a temperature sensor
8. 8.⚡ A cell changes stored chemical energy into which kind of energy? (a) sound energy (b) nuclear energy (c) wind energy (d) electrical energy
9. 9.🔗 Series or parallel circuit: “many paths for current”? (a) series (b) parallel
10. 10.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) stays the same (b) becomes zero (c) gets smaller (d) gets bigger
11. 11.🧩 Which component limits the current? (a) diode (b) resistor (c) fuse (d) motor
12. 12.🧮 A 1.8 V battery is joined to 12 Ω and 6 Ω resistors in series. What current flows (in amperes)? =
13. 13.🔢 To run one loop of a plant-watering program, what comes right after “compare with the limit”? (a) wait a few seconds (b) switch the pump on/off (c) read the soil sensor
14. 14.🔘 Which kind of switch stays where you flip it? (a) a toggle switch (b) a reed switch (c) a slide switch (d) a tilt switch
15. 15.💡 A battery lights 2 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) brighter (c) dimmer
16. 16.🧩 Which part changes electrical energy into movement? (a) an LED (b) a fuse (c) a resistor (d) a motor
17. 17.📏 Which unit measures resistance? (a) volt (V) (b) watt (W) (c) ohm (Ω) (d) ampere (A)
18. 18.True or false: “how loud a sound is” is a digital signal. (a) True (b) False
19. 19.🤖 Microcontroller or laptop: which one runs one small program? (a) microcontroller (b) laptop
20. 20.True or false: “a single current path” is true of a parallel circuit. (a) False (b) True
21. 21.True or false: a doorbell mainly makes movement. (a) True (b) False
22. 22.💡 A red LED uses 2 V and should get 25 mA. It runs from a 12 V supply. What resistor (in ohms) is needed in series?
23. 23.🌈 A gold fourth band on a resistor means the value may be off by … (a) 5 % (b) 25 % (c) 0 % (d) 50 %
24. 24.🧮 Adding another resistor in series makes the total resistance … (a) smaller (b) bigger (c) stay the same (d) zero
25. 25.🔺 A current of 0.2 A flows through a 20 Ω resistor. What is the voltage across it (in volts)? =
26. 26.⚠️ Why must we never touch switches with wet hands? (a) it spoils the paint (b) water carries current (c) water makes it cold (d) it is just untidy
27. 27.🗺️ In an input → process → output plan, is “a button press” the input, the process or the output? (a) input (b) process (c) output
28. 28.🤖 Does a smart watch usually have a microcontroller inside? (a) No (b) Yes
29. 29.🔍 Which is the odd one out? (a) a buzzer (b) a street light (c) a siren (d) a loudspeaker
30. 30.🌈 A resistor has the colour bands violet, orange, brown. What is its value (in ohms)?
31. 31.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 7 LOW
    set pin 7 HIGH
    set pin 7 HIGH
    set pin 8 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
32. 32.🔗 Series or parallel circuit: “a single current path”? (a) parallel (b) series
33. 33.💡 4 identical bulbs are joined in series with a battery and a closed switch on the main wire. All the bulbs are in place. Does bulb 3 glow? (a) No (b) Yes
34. 34.Which of these is an insulator? (a) a plastic straw (b) a brass key (c) a steel coin (d) a steel spoon
35. 35.⚡ Which formula gives electric power? (a) P = V × I (b) P = V ÷ I (c) P = V + I (d) P = I ÷ V
36. 36.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 330 and motion is detected (true). What happens? (a) porch lamp ON (b) porch lamp OFF
37. 37.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 390 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
38. 38.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to a 6.5 V supply. What current flows (in mA)?
39. 39.True or false: a long and a short line is the symbol for a resistor. (a) True (b) False
40. 40.🔘 Two switches are in series. When does the bulb glow? (a) when both are OFF (b) never (c) when both are ON (d) when either is ON

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