Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 240 · 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 drawing is the symbol for a resistor? (a) one tall, one short bar (b) a small empty box (c) a circle with a cross (d) many long-short pairs
2. 2.⚙️ Which actuator would you use to move water to plants? (a) a display (b) a motor (c) a pump (d) a servo motor
3. 3.✏️ In a cell symbol, which line is the + terminal? (a) the longer line (b) the shorter line (c) neither line (d) both lines
4. 4.💡 Does it save or waste electricity to use old filament bulbs? (a) wastes electricity (b) saves electricity
5. 5.True or false: the ammeter is joined across a part. (a) False (b) True
6. 6.🔘 Which kind of switch closes when tipped over? (a) a push button (b) a toggle switch (c) a tilt switch (d) a slide switch
7. 7.💡 6 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. Bulb 5 is taken out of its holder. How many bulbs glow?
8. 8.✏️ Why do engineers draw circuits with symbols? (a) quick and clear for all (b) to hide the circuit (c) to make it colourful (d) symbols are heavier
9. 9.🔐 Is it a good or a risky habit to share only needed data? (a) risky habit (b) good habit
10. 10.🌈 A resistor has the colour bands red, violet, red. What is its value in kilo-ohms (kΩ)? =
11. 11.🔺 A current of 0.1 A flows when 0.4 V is joined across a resistor. What is its resistance (in ohms)?
12. 12.Which of these is not an IoT device? (a) an app-controlled bulb (b) a plain wall switch (c) a Wi-Fi smart plug (d) a Wi-Fi weather station
13. 13.🔺 A 7.5 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
14. 14.🔁 What does a variable do in a program? (a) joins two wires (b) blinks an LED (c) stores a value (d) measures light
15. 15.⚡ A device works on 9 V and takes 0.5 A. What is its power (in watts)? =
16. 16.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 550 ms }
    How many milliseconds does one blink (ON + OFF) take?
17. 17.📏 Voltmeter or ammeter: which one is joined in series? (a) ammeter (b) voltmeter
18. 18.🔺 A current of 1.5 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
19. 19.⏱️ loop forever { LED ON; wait 200 ms; LED OFF; wait 150 ms }
    How many milliseconds does one blink (ON + OFF) take?
20. 20.True or false: “many paths for current” is true of a parallel circuit. (a) True (b) False
21. 21.Which of these is not an IoT device? (a) a pencil sharpener (b) a Wi-Fi weather station (c) a Wi-Fi smart plug (d) a Wi-Fi doorbell camera
22. 22.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) + (positive) (b) − (negative)
23. 23.True or false: to share only needed data is a good habit. (a) False (b) True
24. 24.🧩 Which component is a resistance knob? (a) potentiometer (b) capacitor (c) motor (d) thermistor
25. 25.🔺 A current of 25 mA flows through a 150 Ω resistor. What is the voltage across it (in volts)? =
26. 26.🔁 total = 0
    for i = 1 to 4 { total = total + i }
    What is total at the end?
27. 27.🤖 if (moisture < 40) { pump ON } else { pump OFF }
    The soil moisture sensor reads 48 %. What happens? (a) pump ON (b) pump OFF
28. 28.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 volt (c) 1 watt (d) 1 kilowatt-hour (kWh)
29. 29.True or false: a TV remote usually has a microcontroller inside. (a) False (b) True
30. 30.⚠️ Which power source should children use for electronics projects? (a) an inverter socket (b) a wall socket (c) a mains extension board (d) a small battery pack
31. 31.🌈 A resistor has the colour bands blue, green, red. What is its value (in ohms)?
32. 32.Which job is done by the pins? (a) brings power and code (b) connect sensors and LEDs (c) restarts the program (d) runs the program
33. 33.🔦 A circuit has a used-up (dead) 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 steel spoon. Does the bulb glow? (a) No (b) Yes
34. 34.Which job needs a rain sensor? (a) start a fan when hot (b) warn of a gas leak (c) close a window in rain (d) keep an incubator warm
35. 35.🔋 How many 3 V cells must be joined in series to give 21 V?
36. 36.True or false: to fly a kite near wires is safe. (a) True (b) False
37. 37.🧭 Which part of a microcontroller board shows the board is on? (a) the pins (b) the power LED (c) the main chip (d) the reset button
38. 38.Which of these is true of a series circuit? (a) many paths for current (b) each gets the full volts (c) a single current path (d) own switch for each bulb
39. 39.🔋 How many volts does one ordinary torch cell give? (a) 1.5 V (b) 230 V (c) 0.5 V (d) 15 V
40. 40.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) parallel (b) series

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