Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 607 · 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.🔐 Is it a good or a risky habit to tap unknown app links? (a) good habit (b) risky habit
2. 2.🌐 A soil sensor sends a reading to an app every 10 minutes. How many readings arrive in 5 hours?
3. 3.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) share it with friends (b) ask a parent first (c) post it online (d) type it all in
4. 4.True or false: to reuse one password is a risky habit. (a) False (b) True
5. 5.What does a resistor do? (a) makes a beeping sound (b) senses how hot it is (c) makes things spin (d) limits the current
6. 6.🧮 Two resistors in parallel give a total that is … (a) less than either one (b) more than either one (c) their sum (d) always zero
7. 7.🧩 Which component is a resistance knob? (a) diode (b) transistor (c) LED (d) potentiometer
8. 8.💡 A battery lights 3 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
9. 9.Which of these is an output? (a) a temperature sensor (b) a speaker (c) a keypad (d) a light sensor
10. 10.⚡ A device works on 24 V and takes 2 A. What is its power (in watts)? =
11. 11.🌈 Which band is read first on a resistor? (a) the widest gap (b) the one nearest an end (c) the gold band (d) any band
12. 12.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
13. 13.Which of these is safe? (a) keep drinks far away (b) use mains for a project (c) use a cable with cuts (d) touch a switch when wet
14. 14.⚙️ Which actuator would you use to move water to plants? (a) an LED (b) a buzzer (c) a motor (d) a pump
15. 15.🔁 count = 6
    repeat 8 times { count = count + 4 }
    What is count at the end?
16. 16.True or false: to leave fridge door open wastes electricity. (a) True (b) False
17. 17.Which of these means the circuit is open? (a) the loop is complete (b) a wire has come loose (c) all wires are joined (d) the switch is ON
18. 18.🔺 A current of 2.5 A flows through a 2 Ω resistor. What is the voltage across it (in volts)? =
19. 19.💡 A red LED (it uses 2 V) is joined with a 100 Ω resistor to a 2.5 V supply. What current flows (in mA)?
20. 20.🔐 Is it a good or a risky habit to share only needed data? (a) good habit (b) risky habit
21. 21.✏️ In a circuit diagram, which part is drawn as a circle with M inside? (a) LED (b) cell (c) motor (d) voltmeter
22. 22.🤖 if (light < 200 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 120 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
23. 23.🔁 count = 1
    while (count < 15) { count = count + 2 }
    How many times does the loop run?
24. 24.🔢 To plan an electronics project, which comes first: “draw the circuit diagram” or “pick a problem to solve”? (a) pick a problem to solve (b) draw the circuit diagram
25. 25.📏 Which unit measures voltage? (a) ohm (Ω) (b) volt (V) (c) ampere (A) (d) watt (W)
26. 26.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the input (b) the battery (c) the process (d) the output
27. 27.🔌 Is a rubber eraser a conductor or an insulator? (a) a conductor (b) an insulator
28. 28.Which of these is safe? (a) use mains for a project (b) open a phone charger (c) dry your hands first (d) poke things in a socket
29. 29.Which of these is the output? (a) a temperature reading (b) count button presses (c) the pump turns on (d) a light level reading
30. 30.Which of these mainly makes sound? (a) a rice cooker (b) a mixer grinder (c) a water heater (d) a doorbell
31. 31.🔺 A current of 0.25 A flows when 3 V is joined across a resistor. What is its resistance (in ohms)?
32. 32.Which of these uses electricity? (a) a cell (b) a television (c) a power station (d) a wind turbine
33. 33.What does a push button do? (a) flips up or down (b) springs back when let go (c) closes near a magnet (d) closes when tipped over
34. 34.🔌 Why are electric wires covered in plastic? (a) plastic makes current (b) plastic is an insulator (c) to make them heavy (d) plastic is a conductor
35. 35.True or false: to use daylight to read wastes electricity. (a) True (b) False
36. 36.🔘 A bulb and a cell are joined through 5 switches on 5 side-by-side paths, one switch on each path (parallel). What is the smallest number of switches that must be ON to light the bulb?
37. 37.🌐 Is a fitness band with app an IoT device? (a) an IoT device (b) not an IoT device
38. 38.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) + (positive) (b) − (negative)
39. 39.🔍 Which is the odd one out? (a) dry your hands first (b) take cells out after use (c) use small battery cells (d) use mains for a project
40. 40.Which of these saves electricity? (a) leave fridge door open (b) run fans in empty rooms (c) close the fridge quickly (d) use old filament bulbs

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