Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 319 · 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.✏️ Why do engineers draw circuits with symbols? (a) to hide the circuit (b) to make it colourful (c) quick and clear for all (d) symbols are heavier
2. 2.⏱️ repeat 3 times { buzzer ON; wait 100 ms; buzzer OFF; wait 100 ms }
   How many milliseconds does this take in all?
3. 3.🔍 Which is the odd one out? (a) a temperature sensor (b) a light sensor (c) a keypad (d) a motor
4. 4.🌐 In an IoT system, which part carries the data? (a) Wi-Fi (b) microcontroller (c) sensor (d) actuator
5. 5.🔍 Which is the odd one out? (a) a dry cork (b) an iron nail (c) a graphite rod (d) a copper wire
6. 6.🔘 Which kind of switch stays where you flip it? (a) a slide switch (b) a toggle switch (c) a push button (d) a tilt switch
7. 7.True or false: a table fan mainly makes sound. (a) False (b) True
8. 8.True or false: to set a strong password is a good habit. (a) True (b) False
9. 9.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) capacitor (b) battery (c) bulb (d) resistor
10. 10.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. Does the bulb glow? (a) No (b) Yes
11. 11.True or false: a laptop runs one small program. (a) True (b) False
12. 12.Which job needs a display? (a) move water to plants (b) show the temperature (c) show a status light (d) beep an alarm
13. 13.🤖 Microcontroller or laptop: which one uses very little power? (a) laptop (b) microcontroller
14. 14.🌐 Each reading a sensor sends is 25 bytes. How many bytes do 50 readings take?
15. 15.Which of these is an insulator? (a) a steel spoon (b) a rubber eraser (c) a safety pin (d) a metal paper clip
16. 16.True or false: resistance is measured in amperes (A). (a) False (b) True
17. 17.🔺 A 20 V supply is joined across an 8 Ω resistor. What current flows (in amperes)? =
18. 18.📶 Digital or analog: HIGH or LOW only? (a) analog (b) digital
19. 19.Which drawing is the symbol for a motor? (a) a straight line (b) a dot where wires meet (c) a circle with M inside (d) a line lifted at a gap
20. 20.🔁 What does a variable do in a program? (a) measures light (b) joins two wires (c) blinks an LED (d) stores a value
21. 21.💡 5 identical bulbs are joined in parallel across a 1.5 V battery (ideal wires). How many volts does each bulb get? =
22. 22.🔢 To plan an electronics project, which comes first: “build it with an adult” or “test it and fix it”? (a) build it with an adult (b) test it and fix it
23. 23.💡 What happens if an LED is put in backwards? (a) it changes colour (b) it makes a sound (c) it lights brighter (d) it does not light
24. 24.Which of these mainly gives out heat? (a) a ceiling fan (b) a traffic signal (c) an electric kettle (d) a loudspeaker
25. 25.🌈 In the resistor colour code, which number does grey stand for?
26. 26.True or false: to switch off empty rooms saves electricity. (a) True (b) False
27. 27.True or false: “a break stops every bulb” is true of a series circuit. (a) True (b) False
28. 28.⚠️ A cell gets hot when its + and − ends are joined by a bare wire. What is this called? (a) a safe circuit (b) a parallel circuit (c) a short circuit (d) an open circuit
29. 29.🌐 Is a battery torch an IoT device? (a) not an IoT device (b) an IoT device
30. 30.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 8 HIGH
    set pin 7 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
31. 31.⚡ What do we call a flow of electric charge through a wire? (a) a magnet (b) sound (c) electric current (d) friction
32. 32.🌈 A resistor has the colour bands green, green, yellow. What is its value in kilo-ohms (kΩ)? =
33. 33.Which of these is an insulator? (a) a graphite rod (b) aluminium foil (c) a copper wire (d) a glass marble
34. 34.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) straight lines (c) dotted circles (d) wavy lines
35. 35.🔌 Is a steel spoon a conductor or an insulator? (a) an insulator (b) a conductor
36. 36.🌈 A resistor has the colour bands brown, blue, orange. What is its value in kilo-ohms (kΩ)? =
37. 37.🧭 Which part of a microcontroller board shows the board is on? (a) the reset button (b) the main chip (c) the USB port (d) the power LED
38. 38.True or false: a reed switch stays where you flip it. (a) True (b) False
39. 39.🧮 A 47 Ω resistor is joined in series with two equal 470 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
40. 40.⚠️ Why must we never touch switches with wet hands? (a) water makes it cold (b) it is just untidy (c) it spoils the paint (d) water carries current

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