← Final electronics test lesson New set →

Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 284 · 40 questions
TalentJR

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.

NameDateTime takenScore ___ / 40
  1. 1.💡 On an LED, is the shorter leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
  2. 2.🌐 Each reading a sensor sends is 20 bytes. How many bytes do 200 readings take?
  3. 3.🔘 When a switch is ON, the circuit is … (a) closed (b) cut (c) open (d) broken
  4. 4.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a copper wire across the gap. Does the bulb glow? (a) No (b) Yes
  5. 5.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
  6. 6.🔁 total = 0
    for i = 1 to 10 { total = total + i }
    What is total at the end?
  7. 7.Which of these mainly gives out light? (a) a traffic signal (b) a table fan (c) an electric drill (d) an electric kettle
  8. 8.🔌 Is aluminium foil a conductor or an insulator? (a) an insulator (b) a conductor
  9. 9.🤖 if (temperature > 30) { show “Hot” } else if (temperature > 19) { show “Warm” } else { show “Cool” }
    The temperature is 19 °C. What is shown?     (a) Hot (b) Warm (c) Cool
  10. 10.🔍 Which is the odd one out? (a) change default passwords (b) read app permissions (c) accept every permission (d) install software updates
  11. 11.Which of these is true of a series circuit? (a) own switch for each bulb (b) one out, the rest glow (c) a single current path (d) used in house wiring
  12. 12.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 21) { show “Warm” } else { show “Cool” }
    The temperature is 42 °C. What is shown?     (a) Cool (b) Hot (c) Warm
  13. 13.🔍 Which is the odd one out? (a) close the fridge quickly (b) set the AC to 24 °C (c) run fans in empty rooms (d) use daylight to read
  14. 14.🧾 A 50 W appliance runs for 2 hours. How many units (kWh) of electricity does it use? =
  15. 15.⏱️ A program says “wait 1250 ms”. How many seconds is that? =
  16. 16.🤖 What is a microcontroller? (a) a kind of bulb (b) a type of battery (c) a big desktop computer (d) a computer on one chip
  17. 17.🔺 A 16 V supply is joined across a 400 Ω resistor. What current flows (in milliamperes, mA)?
  18. 18.🌈 In the resistor colour code, which number does violet stand for?
  19. 19.📏 Voltmeter or ammeter: which one measures voltage? (a) voltmeter (b) ammeter
  20. 20.🔋 3 identical 3 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
  21. 21.🔢 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
  22. 22.🌐 In an IoT system, which part stores data online? (a) microcontroller (b) cloud server (c) phone app (d) sensor
  23. 23.⏱️ repeat 8 times { buzzer ON; wait 700 ms; buzzer OFF; wait 100 ms }
    How many milliseconds does this take in all?
  24. 24.🧮 Two equal 100 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
  25. 25.🧩 A capacitor in a circuit can … (a) measure heat (b) make light (c) spin a wheel (d) store charge briefly
  26. 26.🤖 if (moisture < 50) { pump ON } else { pump OFF }
    The soil moisture sensor reads 49 %. What happens?     (a) pump OFF (b) pump ON
  27. 27.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
  28. 28.📶 Digital or analog: how loud a sound is? (a) analog (b) digital
  29. 29.✏️ Why do engineers draw circuits with symbols? (a) to hide the circuit (b) quick and clear for all (c) to make it colourful (d) symbols are heavier
  30. 30.🔌 Is an iron nail a conductor or an insulator? (a) a conductor (b) an insulator
  31. 31.🤖 if (temperature > 31) { show “Hot” } else if (temperature > 21) { show “Warm” } else { show “Cool” }
    The temperature is 23 °C. What is shown?     (a) Cool (b) Hot (c) Warm
  32. 32.🔁 What must there be for a current to flow? (a) a plastic gap (b) a complete loop (c) a broken path (d) one loose end
  33. 33.🌈 Which band is read first on a resistor? (a) the one nearest an end (b) the widest gap (c) any band (d) the gold band
  34. 34.🔺 In the V-I-R triangle, how do we find I? (a) I = V + R (b) I = V × R (c) I = V ÷ R (d) I = R ÷ V
  35. 35.True or false: a reed switch closes near a magnet. (a) False (b) True
  36. 36.Which of these saves electricity? (a) leave the TV on standby (b) iron one shirt at a time (c) use old filament bulbs (d) use daylight to read
  37. 37.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 LOW
    Is the LED ON or OFF at the end?     (a) OFF (b) ON
  38. 38.🔘 Which kind of switch springs back when let go? (a) a toggle switch (b) a slide switch (c) a push button (d) a reed switch
  39. 39.⚡ What do we call a flow of electric charge through a wire? (a) electric current (b) a magnet (c) friction (d) sound
  40. 40.📏 How many amperes (A) is 2120 mA? =

Answer key

  1. cathode (−)
  2. 4000
  3. closed
  4. Yes
  5. + (positive)
  6. 55
  7. a traffic signal
  8. a conductor
  9. Cool
  10. accept every permission
  11. a single current path
  12. Hot
  13. run fans in empty rooms
  14. 0.1
  15. 1.25
  16. a computer on one chip
  17. 40
  18. 7
  19. voltmeter
  20. 9
  21. pick a problem to solve
  22. cloud server
  23. 6400
  24. 50
  25. store charge briefly
  26. pump ON
  27. 345
  28. analog
  29. quick and clear for all
  30. a conductor
  31. Warm
  32. a complete loop
  33. the one nearest an end
  34. I = V ÷ R
  35. True
  36. use daylight to read
  37. ON
  38. a push button
  39. electric current
  40. 2.12

Free electronics lessons, practice and worksheets at talentjr.in/electronics-for-kids