Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 519 · 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.🤖 if (temperature > 34) { show “Hot” } else if (temperature > 25) { show “Warm” } else { show “Cool” }
   The temperature is 40 °C. What is shown? (a) Cool (b) Warm (c) Hot
2. 2.🔁 Is the circuit closed or open if the switch is ON? (a) open (b) closed
3. 3.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) + (positive) (b) − (negative)
4. 4.True or false: “a soil moisture reading” is the input. (a) True (b) False
5. 5.🔌 Is a push button an input or an output for a microcontroller? (a) input (b) output
6. 6.⏱️ loop forever { LED ON; wait 350 ms; LED OFF; wait 100 ms }
   How many milliseconds does one blink (ON + OFF) take?
7. 7.🔍 Which is the odd one out? (a) a keypad (b) a speaker (c) a small display (d) a buzzer
8. 8.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a steel spoon across the gap. Does the bulb glow? (a) Yes (b) No
9. 9.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 9 minutes?
10. 10.True or false: “one bulb out, all go out” is true of a parallel circuit. (a) False (b) True
11. 11.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 18) { show “Warm” } else { show “Cool” }
    The temperature is 40 °C. What is shown? (a) Hot (b) Cool (c) Warm
12. 12.⚡ A device works on 6 V and takes 1.5 A. What is its power (in watts)? =
13. 13.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) only one (b) both of them (c) none (d) it does not matter
14. 14.⏱️ What does “wait 500 ms” do? (a) turns the LED off (b) blinks 500 times (c) waits 500 seconds (d) pauses for half a second
15. 15.🌐 How does a home IoT device usually send its data to the app? (a) by post (b) over Wi-Fi (c) by shouting (d) through a candle
16. 16.Which drawing is the symbol for a cell? (a) one tall, one short bar (b) a circle with A inside (c) a circle with an X in it (d) a line lifted at a gap
17. 17.🔋 Cells joined + to − in a row (series) give … (a) a bigger voltage (b) no voltage (c) the same voltage (d) a smaller voltage
18. 18.🧩 Which component makes a beeping sound? (a) buzzer (b) resistor (c) motor (d) LDR
19. 19.🧮 Five equal 25 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
20. 20.Which drawing is the symbol for a bulb? (a) one tall, one short bar (b) triangle against a bar (c) two equal parallel lines (d) a circle with an X in it
21. 21.Which drawing is the symbol for a diode? (a) one tall, one short bar (b) a straight line (c) a dot where wires meet (d) triangle against a bar
22. 22.⚡ Power tells us … (a) the size of a cell (b) energy used each second (c) the colour of light (d) the length of a wire
23. 23.💡 A battery lights 4 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) brighter (c) the same
24. 24.🔺 A current of 1.5 A flows through a 6 Ω resistor. What is the voltage across it (in volts)? =
25. 25.🔺 A current of 10 mA flows through a 250 Ω resistor. What is the voltage across it (in volts)? =
26. 26.🔋 Does an air conditioner give electricity or use electricity? (a) gives electricity (b) uses electricity
27. 27.🔐 Privacy for a smart device means controlling … (a) its colour (b) its battery size (c) how loud it beeps (d) who can see your data
28. 28.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a wooden stick. Does the bulb glow? (a) Yes (b) No
29. 29.Which job is done by the main chip? (a) connect sensors and LEDs (b) brings power and code (c) keeps the voltage steady (d) runs the program
30. 30.True or false: to post your live location is a risky habit. (a) False (b) True
31. 31.🔁 Is the circuit closed or open if a wire has come loose? (a) open (b) closed
32. 32.🧮 Resistors of 20 Ω and 33 Ω are joined in series. What is the total resistance (in ohms)?
33. 33.Which of these is the process? (a) an LED lights up (b) decide if soil is dry (c) an alert on the phone (d) a temperature reading
34. 34.📏 Voltmeter or ammeter: which one measures voltage? (a) ammeter (b) voltmeter
35. 35.🌈 Which band is read first on a resistor? (a) the gold band (b) any band (c) the widest gap (d) the one nearest an end
36. 36.💡 Does it save or waste electricity to switch off empty rooms? (a) wastes electricity (b) saves electricity
37. 37.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) stay the same (c) smaller (d) bigger
38. 38.⚡ A home appliance on the 230 V mains takes 2 A. What is its power (in watts)?
39. 39.True or false: if the loop is complete, the circuit is open and no current flows. (a) False (b) True
40. 40.🔐 Is it a good or a risky habit to set a strong password? (a) risky habit (b) good habit

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