Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 88 · 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 > 33) { show “Hot” } else if (temperature > 18) { show “Warm” } else { show “Cool” }
   The temperature is 10 °C. What is shown? (a) Warm (b) Cool (c) Hot
2. 2.💡 An LED is joined to a 6 V battery through a 1000 Ω resistor; the leg next to the flat edge of its rim goes to the + side. What happens? (a) does not light (b) lights up (c) may burn out
3. 3.🔍 Which is the odd one out? (a) check if temp > 30 (b) decide if soil is dry (c) an LED lights up (d) compare with a limit
4. 4.True or false: a laptop runs one small program. (a) False (b) True
5. 5.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a paper strip across the gap. Does the bulb glow? (a) Yes (b) No
6. 6.🔍 Which is the odd one out? (a) count button presses (b) decide if soil is dry (c) check if temp > 30 (d) the fan starts
7. 7.True or false: a transistor lets current go one way. (a) True (b) False
8. 8.True or false: the ammeter is joined in series. (a) False (b) True
9. 9.⚡ A device works on 6 V and takes 0.5 A. What is its power (in watts)? =
10. 10.🤖 Which is a safe power source for a beginner microcontroller board? (a) a wall socket directly (b) bare mains wires (c) a 230 V cable (d) USB or a 9 V battery
11. 11.Which job is done by the reset button? (a) keeps the voltage steady (b) brings power and code (c) restarts the program (d) shows the board is on
12. 12.🧮 Resistors of 220 Ω, 33 Ω, 100 Ω and 10 Ω are joined in series. What is the total resistance (in ohms)?
13. 13.What does a resistor do? (a) lets current go one way (b) has coloured bands (c) glows using little power (d) makes things spin
14. 14.🤖 if (sound > 80) { red LED ON } else { green LED ON }
    The sound sensor reads 71. What happens? (a) green LED ON (b) red LED ON
15. 15.🔺 A 0.4 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
16. 16.⏱️ loop forever { LED ON; wait 900 ms; LED OFF; wait 850 ms }
    How many milliseconds does one blink (ON + OFF) take?
17. 17.True or false: to touch a switch when wet is safe. (a) True (b) False
18. 18.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a plastic ruler across the gap. Does the bulb glow? (a) No (b) Yes
19. 19.🧮 A 2.5 V battery is joined to 3 Ω and 2 Ω resistors in series. What current flows (in amperes)? =
20. 20.🌈 A resistor has the colour bands green, grey, orange. What is its value in kilo-ohms (kΩ)? =
21. 21.🔍 Which is the odd one out? (a) a siren (b) a buzzer (c) a school bell (d) an electric drill
22. 22.Which job is done by the pins? (a) connect sensors and LEDs (b) brings power and code (c) keeps the voltage steady (d) shows the board is on
23. 23.Which of these mainly gives out light? (a) a water heater (b) an electric toy car (c) a loudspeaker (d) a traffic signal
24. 24.True or false: a circle with a cross is the symbol for a bulb. (a) False (b) True
25. 25.True or false: an electric toy car mainly gives out light. (a) True (b) False
26. 26.⏱️ How many milliseconds is a wait of 0.3 seconds?
27. 27.✏️ In a cell symbol, which line is the + terminal? (a) both lines (b) neither line (c) the shorter line (d) the longer line
28. 28.🔍 Which is the odd one out? (a) a steel spoon (b) a glass marble (c) a graphite rod (d) a copper wire
29. 29.🔐 Privacy for a smart device means controlling … (a) its battery size (b) who can see your data (c) its colour (d) how loud it beeps
30. 30.🔋 How many volts does one ordinary torch cell give? (a) 230 V (b) 15 V (c) 1.5 V (d) 0.5 V
31. 31.Which of these mainly makes sound? (a) an electric toy car (b) a night lamp (c) a mixer grinder (d) a loudspeaker
32. 32.What does a push button do? (a) closes near a magnet (b) springs back when let go (c) stays where you flip it (d) closes when tipped over
33. 33.True or false: to set a strong password is a risky habit. (a) True (b) False
34. 34.🔺 A current of 40 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
35. 35.⚡ An 18 W device works on 6 V. What current does it take (in amperes)? =
36. 36.⏱️ What does “wait 500 ms” do? (a) waits 500 seconds (b) blinks 500 times (c) pauses for half a second (d) turns the LED off
37. 37.🔺 A current of 0.1 A flows through a 2 Ω resistor. What is the voltage across it (in volts)? =
38. 38.🔁 What does “count = count + 1” do? (a) takes 1 away (b) prints 1 (c) sets count to 1 (d) adds 1 to count
39. 39.🌐 A weather station sends one reading every 5 seconds. How many readings does it send in 3 minutes?
40. 40.📏 How many milliamperes (mA) is 2.11 A?

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