Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 23 · 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 an IoT system, which part measures the real world? (a) phone app (b) cloud server (c) actuator (d) sensor
2. 2.Which of these wastes electricity? (a) use LED lamps (b) close the fridge quickly (c) use daylight to read (d) run fans in empty rooms
3. 3.🔍 Which is the odd one out? (a) a Wi-Fi doorbell camera (b) an app-controlled bulb (c) a Wi-Fi smart plug (d) a battery torch
4. 4.True or false: to start a fan when hot, use a temperature sensor. (a) False (b) True
5. 5.🧩 Which component senses how bright it is? (a) transistor (b) LDR (c) buzzer (d) motor
6. 6.🔍 Which is the odd one out? (a) a light level reading (b) a soil moisture reading (c) a temperature reading (d) the pump turns on
7. 7.🔋 4 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)? =
8. 8.🧩 A capacitor in a circuit can … (a) spin a wheel (b) make light (c) store charge briefly (d) measure heat
9. 9.🔌 Is a ceramic cup a conductor or an insulator? (a) an insulator (b) a conductor
10. 10.What does a slide switch do? (a) springs back when let go (b) closes near a magnet (c) slides side to side (d) stays where you flip it
11. 11.⚡ A device works on 24 V and takes 0.5 A. What is its power (in watts)? =
12. 12.⚠️ Why must we never touch switches with wet hands? (a) it is just untidy (b) water carries current (c) it spoils the paint (d) water makes it cold
13. 13.🔋 Cells joined + to − in a row (series) give … (a) a bigger voltage (b) the same voltage (c) no voltage (d) a smaller voltage
14. 14.🔢 To plan an electronics project, which comes first: “build it with an adult” or “test it and fix it”? (a) test it and fix it (b) build it with an adult
15. 15.✏️ In a cell symbol, which line is the + terminal? (a) the shorter line (b) the longer line (c) neither line (d) both lines
16. 16.🔺 A 36 V supply is joined across a 12 Ω resistor. What current flows (in amperes)? =
17. 17.What does a tilt switch do? (a) closes when tipped over (b) works only while pressed (c) closes near a magnet (d) flips up or down
18. 18.🔋 Does a generator give electricity or use electricity? (a) uses electricity (b) gives electricity
19. 19.🔗 Series or parallel circuit: “each gets the full volts”? (a) parallel (b) series
20. 20.Which of these is an output? (a) a servo motor (b) a sound sensor (c) a turning knob (d) a temperature sensor
21. 21.🔋 What is a battery? (a) a kind of bulb (b) two or more cells joined (c) a switch with a lid (d) one single wire
22. 22.🔁 What does a variable do in a program? (a) joins two wires (b) measures light (c) stores a value (d) blinks an LED
23. 23.Which drawing is the symbol for a bulb? (a) two or more cell symbols (b) a circle with a cross (c) two equal parallel lines (d) a line lifted at a gap
24. 24.🔢 To run one loop of a plant-watering program, what comes right after “read the soil sensor”? (a) wait a few seconds (b) switch the pump on/off (c) compare with the limit
25. 25.Which of these is an output? (a) a motor (b) a motion sensor (c) a push button (d) a keypad
26. 26.Which of these is a risky habit? (a) post your live location (b) share only needed data (c) install software updates (d) turn off unused gadgets
27. 27.🔋 How many volts does one ordinary torch cell give? (a) 0.5 V (b) 230 V (c) 1.5 V (d) 15 V
28. 28.🔋 5 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)? =
29. 29.📏 How many kilowatts (kW) is 1250 W? =
30. 30.Which of these is an IoT device? (a) a plain table fan (b) a Wi-Fi doorbell camera (c) a plain wall switch (d) a battery torch
31. 31.Which of these is true of a series circuit? (a) own switch for each bulb (b) many paths for current (c) one bulb out, all go out (d) each gets the full volts
32. 32.Which of these is an input? (a) a light sensor (b) a servo motor (c) a buzzer (d) an LED
33. 33.True or false: if the switch is ON, the circuit is open and no current flows. (a) False (b) True
34. 34.🌐 Is a smart energy meter an IoT device? (a) an IoT device (b) not an IoT device
35. 35.True or false: a spinning top usually has a microcontroller inside. (a) False (b) True
36. 36.Which drawing is the symbol for a switch? (a) a dot where wires meet (b) a line lifted at a gap (c) a circle with a cross (d) a circle with M inside
37. 37.⚡ Which formula gives electric power? (a) P = V × I (b) P = V + I (c) P = I ÷ V (d) P = V ÷ I
38. 38.💡 2 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 1 is taken out of its holder. How many bulbs glow?
39. 39.🧮 Two resistors in parallel give a total that is … (a) always zero (b) less than either one (c) more than either one (d) their sum
40. 40.Which of these is measured in amperes (A)? (a) power (b) the flow of charge (c) energy used each second (d) how much a part resists

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