Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 903 · 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 is the odd one out? (a) stop if a part gets hot (b) fly kites in open fields (c) use small battery cells (d) touch a fallen wire
2. 2.True or false: to make a parking alarm, use a distance sensor. (a) False (b) True
3. 3.🧮 Resistors of 10 Ω, 10 Ω and 20 Ω are joined in series. What is the total resistance (in ohms)?
4. 4.True or false: to start a fan when hot, use a rain sensor. (a) True (b) False
5. 5.🔺 A current of 1.5 A flows through a 4 Ω resistor. What is the voltage across it (in volts)? =
6. 6.True or false: “used in house wiring” is true of a series circuit. (a) True (b) False
7. 7.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) none (b) it does not matter (c) only one (d) both of them
8. 8.⏱️ A program says “wait 5000 ms”. How many seconds is that? =
9. 9.Which of these is the input? (a) a temperature reading (b) decide if soil is dry (c) check if temp > 30 (d) compare with a limit
10. 10.Which drawing is the symbol for a resistor? (a) a circle with M inside (b) a plain rectangle (c) a circle with an X in it (d) a circle with a cross
11. 11.True or false: on a cell, “the end with a bump” means the − (negative) end. (a) True (b) False
12. 12.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
13. 13.⚠️ Is it safe to touch a switch when wet? (a) not safe (b) safe
14. 14.Which of these uses electricity? (a) a solar panel (b) a generator (c) a computer (d) a cell
15. 15.🔐 Who should decide which smart devices go in a child’s room? (a) nobody at all (b) an online stranger (c) a parent or guardian (d) the app’s adverts
16. 16.🔍 Which is the odd one out? (a) stay away from pylons (b) fly kites in open fields (c) fly a kite near wires (d) dry your hands first
17. 17.🔁 repeat 5 times { repeat 4 times { beep } }
    How many beeps are there?
18. 18.Which of these uses electricity? (a) a water pump (b) a bicycle dynamo (c) a wind turbine (d) a solar panel
19. 19.🔺 A 4.4 V supply is joined across a 220 Ω resistor. What current flows (in milliamperes, mA)?
20. 20.🔺 In the V-I-R triangle, how do we find I? (a) I = V × R (b) I = V ÷ R (c) I = V + R (d) I = R ÷ V
21. 21.True or false: to fly kites in open fields is not safe. (a) True (b) False
22. 22.🤖 if (temperature > 37) { show “Hot” } else if (temperature > 20) { show “Warm” } else { show “Cool” }
    The temperature is 15 °C. What is shown? (a) Hot (b) Warm (c) Cool
23. 23.🧮 Five equal 50 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
24. 24.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
25. 25.🌐 In an IoT system, which part stores data online? (a) actuator (b) microcontroller (c) cloud server (d) phone app
26. 26.True or false: an electric drill mainly makes movement. (a) False (b) True
27. 27.⚡ What does a toaster mainly change electricity into? (a) sound (b) light (c) heat (d) movement
28. 28.🗺️ Before building a project, what should you write down first? (a) nothing at all (b) inputs and outputs (c) the box colour (d) the final price
29. 29.🔗 Series or parallel circuit: “one bulb out, all go out”? (a) parallel (b) series
30. 30.🌈 A resistor has the colour bands brown, white, red. What is its value (in ohms)?
31. 31.🔢 To run one loop of a plant-watering program, which comes first: “wait a few seconds” or “read the soil sensor”? (a) read the soil sensor (b) wait a few seconds
32. 32.🔺 In the V-I-R triangle, how do we find V? (a) V = I ÷ R (b) V = R ÷ I (c) V = I × R (d) V = I + R
33. 33.🔺 In the V-I-R triangle, how do we find R? (a) R = V ÷ I (b) R = I ÷ V (c) R = V + I (d) R = V × I
34. 34.🔌 Is a speaker an input or an output for a microcontroller? (a) input (b) output
35. 35.Which drawing is the symbol for a wire? (a) a circle with an X in it (b) one tall, one short bar (c) a circle with V inside (d) a straight line
36. 36.🔺 A current of 20 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
37. 37.🔁 Is the circuit closed or open if a wire has come loose? (a) closed (b) open
38. 38.🔁 What does a variable do in a program? (a) stores a value (b) joins two wires (c) measures light (d) blinks an LED
39. 39.🤖 Microcontroller or laptop: which one runs one small program? (a) laptop (b) microcontroller
40. 40.True or false: “bulbs share the voltage” is true of a parallel circuit. (a) True (b) False

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