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Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 417 · 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.🤖 if (moisture < 40) { pump ON } else { pump OFF }
    The soil moisture sensor reads 38 %. What happens?     (a) pump ON (b) pump OFF
  2. 2.✏️ In a circuit diagram, which part is drawn as a line lifted at a gap? (a) voltmeter (b) switch (c) capacitor (d) battery
  3. 3.True or false: current is measured in ohms (Ω). (a) False (b) True
  4. 4.🔁 count = 0
    while (count < 12) { count = count + 3 }
    How many times does the loop run?
  5. 5.True or false: to leave fridge door open saves electricity. (a) False (b) True
  6. 6.⚠️ Is it safe to open a phone charger? (a) not safe (b) safe
  7. 7.💡 A red LED uses 2 V and should get 25 mA. It runs from a 5 V supply. What resistor (in ohms) is needed in series?
  8. 8.📏 Which unit measures resistance? (a) ampere (A) (b) watt (W) (c) ohm (Ω) (d) volt (V)
  9. 9.🌐 Is a smart energy meter an IoT device? (a) an IoT device (b) not an IoT device
  10. 10.🔁 What does a variable do in a program? (a) joins two wires (b) stores a value (c) blinks an LED (d) measures light
  11. 11.Which of these means the circuit is closed? (a) the bulb is unscrewed (b) the switch is OFF (c) a wire is cut (d) the loop is complete
  12. 12.🔍 Which is the odd one out? (a) keep drinks far away (b) fly a kite near wires (c) dry your hands first (d) build with an adult near
  13. 13.💡 An LED is joined to a 9 V battery with no resistor; the leg next to the flat edge of its rim goes to the − side. What happens? (a) may burn out (b) does not light (c) lights up
  14. 14.📶 How many states can a digital pin have? (a) ten (b) a thousand (c) two (d) one
  15. 15.⏱️ loop forever { LED ON; wait 50 ms; LED OFF; wait 350 ms }
    How many times does the LED blink in 20 seconds?
  16. 16.🔋 A 9 V battery and one 1.5 V cell are joined in series, all facing the same way. What is the total voltage (in volts)? =
  17. 17.🌐 Is a battery torch an IoT device? (a) an IoT device (b) not an IoT device
  18. 18.Which drawing is the symbol for a cell? (a) a circle with M inside (b) a straight line (c) a long and a short line (d) a plain rectangle
  19. 19.True or false: a plain wall switch has no microcontroller inside. (a) False (b) True
  20. 20.⚡ What does an electric iron mainly change electricity into? (a) light (b) sound (c) movement (d) heat
  21. 21.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
  22. 22.🔁 x = 2
    repeat 2 times { x = x × 2 }
    What is x at the end?
  23. 23.True or false: “how loud a sound is” is an analog signal. (a) True (b) False
  24. 24.True or false: a plastic straw is an insulator. (a) False (b) True
  25. 25.🔍 Which is the odd one out? (a) change default passwords (b) set a strong password (c) set up with a parent (d) share camera links
  26. 26.🔺 In the V-I-R triangle, how do we find V? (a) V = R ÷ I (b) V = I + R (c) V = I × R (d) V = I ÷ R
  27. 27.⚡ A device works on 1.5 V and takes 1 A. What is its power (in watts)? =
  28. 28.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
    set pin 8 LOW
    set pin 7 HIGH
    set pin 8 HIGH
    set pin 8 HIGH
    Is the LED ON or OFF at the end?     (a) ON (b) OFF
  29. 29.🤖 if (temperature > 35) { show “Hot” } else if (temperature > 22) { show “Warm” } else { show “Cool” }
    The temperature is 18 °C. What is shown?     (a) Hot (b) Cool (c) Warm
  30. 30.True or false: a bicycle bell has no microcontroller inside. (a) True (b) False
  31. 31.⏱️ loop forever { LED ON; wait 900 ms; LED OFF; wait 350 ms }
    How many milliseconds does one blink (ON + OFF) take?
  32. 32.🔍 Which is the odd one out? (a) an LED lights up (b) the fan starts (c) an alert on the phone (d) a temperature reading
  33. 33.True or false: “the fan starts” is the input. (a) True (b) False
  34. 34.🤖 if (light < 300 OR motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 490 and motion is not detected (false). What happens?     (a) porch lamp ON (b) porch lamp OFF
  35. 35.🔐 Is it a good or a risky habit to share only needed data? (a) risky habit (b) good habit
  36. 36.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
  37. 37.True or false: the voltmeter is joined across a part. (a) False (b) True
  38. 38.🗺️ In an input → process → output plan, is “the fan starts” the input, the process or the output? (a) input (b) process (c) output
  39. 39.🔁 count = 2
    repeat 4 times { count = count + 6 }
    What is count at the end?
  40. 40.🔺 A current of 25 mA flows through a 220 Ω resistor. What is the voltage across it (in volts)? =

Answer key

  1. pump ON
  2. switch
  3. False
  4. 4
  5. False
  6. not safe
  7. 120
  8. ohm (Ω)
  9. an IoT device
  10. stores a value
  11. the loop is complete
  12. fly a kite near wires
  13. may burn out
  14. two
  15. 50
  16. 10.5
  17. not an IoT device
  18. a long and a short line
  19. True
  20. heat
  21. 345
  22. 8
  23. True
  24. True
  25. share camera links
  26. V = I × R
  27. 1.5
  28. ON
  29. Cool
  30. True
  31. 1250
  32. a temperature reading
  33. False
  34. porch lamp OFF
  35. good habit
  36. parallel
  37. True
  38. output
  39. 26
  40. 5.5

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