Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 835 · 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.🧭 Which part of a microcontroller board runs the program? (a) the reset button (b) the main chip (c) the power LED (d) the USB port
2. 2.🔋 Does a wind turbine give electricity or use electricity? (a) gives electricity (b) uses electricity
3. 3.🔺 A current of 0.25 A flows through a 12 Ω resistor. What is the voltage across it (in volts)? =
4. 4.⚠️ Is it safe to touch a fallen wire? (a) not safe (b) safe
5. 5.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the input (b) the output (c) the battery (d) the process
6. 6.🔌 Is a brass key a conductor or an insulator? (a) an insulator (b) a conductor
7. 7.🔍 Which is the odd one out? (a) a motion sensor signal (b) compare with a limit (c) a soil moisture reading (d) a button press
8. 8.🌈 A resistor has the colour bands yellow, orange, black. What is its value (in ohms)?
9. 9.Which of these usually has a microcontroller inside? (a) a wind-up toy (b) a candle (c) a hand pump (d) a digital thermometer
10. 10.⚡ Which formula gives electric power? (a) P = V + I (b) P = V × I (c) P = I ÷ V (d) P = V ÷ I
11. 11.🔁 What does a variable do in a program? (a) blinks an LED (b) joins two wires (c) measures light (d) stores a value
12. 12.⚡ A device works on 6 V and takes 0.25 A. What is its power (in watts)? =
13. 13.🔋 6 identical 2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
14. 14.⚡ What does an electric toy car mainly change electricity into? (a) sound (b) light (c) heat (d) movement
15. 15.🧩 A capacitor in a circuit can … (a) measure heat (b) spin a wheel (c) store charge briefly (d) make light
16. 16.🌈 A resistor has the colour bands blue, blue, black. What is its value (in ohms)?
17. 17.🔺 A current of 1.5 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
18. 18.🔍 Which is the odd one out? (a) a siren (b) a school bell (c) a buzzer (d) a tube light
19. 19.🌐 A weather station sends one reading every 10 seconds. How many readings does it send in 9 minutes?
20. 20.🧮 Four equal 40 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
21. 21.🌈 A gold fourth band on a resistor means the value may be off by … (a) 25 % (b) 0 % (c) 5 % (d) 50 %
22. 22.🤖 Microcontroller or laptop: which one needs much more power? (a) laptop (b) microcontroller
23. 23.🤖 When the main loop of a microcontroller program ends, what happens? (a) it starts again (b) the board breaks (c) it deletes itself (d) it stops forever
24. 24.🔋 6 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
25. 25.⚠️ Is it safe to stay away from pylons? (a) safe (b) not safe
26. 26.True or false: a smart watch has no microcontroller inside. (a) True (b) False
27. 27.🔍 Which is the odd one out? (a) install software updates (b) change default passwords (c) log out of shared phones (d) tap unknown app links
28. 28.True or false: an electric drill mainly makes movement. (a) False (b) True
29. 29.🔢 To run one loop of a plant-watering program, which comes first: “switch the pump on/off” or “wait a few seconds”? (a) wait a few seconds (b) switch the pump on/off
30. 30.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
31. 31.🌐 A weather station sends one reading every 60 seconds. How many readings does it send in 9 minutes?
32. 32.Which of these is true of a parallel circuit? (a) bulbs share the voltage (b) a break stops every bulb (c) a single current path (d) many paths for current
33. 33.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) False (b) True
34. 34.🧾 A 40 W filament bulb is swapped for a 6 W LED lamp that gives about the same light. Both would run for 10 hours. How many watt-hours (Wh) are saved?
35. 35.🧮 Two resistors in parallel give a total that is … (a) their sum (b) less than either one (c) more than either one (d) always zero
36. 36.True or false: to change default passwords is a risky habit. (a) True (b) False
37. 37.🤖 if (moisture < 30) { pump ON } else { pump OFF }
    The soil moisture sensor reads 47 %. What happens? (a) pump ON (b) pump OFF
38. 38.🔁 Is the circuit closed or open if a wire is cut? (a) closed (b) open
39. 39.✏️ In a circuit diagram, which part is drawn as a small empty box? (a) resistor (b) bulb (c) capacitor (d) junction
40. 40.🧮 Four equal 100 Ω resistors are joined in parallel. What is the total resistance (in ohms)?

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