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Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 951 · 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.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) bigger (c) smaller (d) stay the same
  2. 2.⏱️ loop forever { LED ON; wait 600 ms; LED OFF; wait 1400 ms }
    How many times does the LED blink in 4 seconds?
  3. 3.💡 What happens if an LED is put in backwards? (a) it makes a sound (b) it changes colour (c) it lights brighter (d) it does not light
  4. 4.True or false: to build with an adult near is not safe. (a) True (b) False
  5. 5.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 170 and motion is not detected (false). What happens?     (a) porch lamp OFF (b) porch lamp ON
  6. 6.⚠️ Is it safe to open a phone charger? (a) safe (b) not safe
  7. 7.🧮 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
  8. 8.🔍 Which is the odd one out? (a) accept every permission (b) reuse one password (c) log out of shared phones (d) tap unknown app links
  9. 9.🔋 What is a battery? (a) two or more cells joined (b) a switch with a lid (c) one single wire (d) a kind of bulb
  10. 10.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
  11. 11.True or false: “one bulb out, all go out” is true of a parallel circuit. (a) False (b) True
  12. 12.Which of these is a risky habit? (a) cover unused cameras (b) turn off unused gadgets (c) post your live location (d) install software updates
  13. 13.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
  14. 14.🤖 if (distance < 20) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 20 cm. What happens?     (a) buzzer is silent (b) buzzer beeps
  15. 15.True or false: to poke things in a socket is safe. (a) True (b) False
  16. 16.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the else part (b) both parts (c) the if part (d) neither part
  17. 17.🔺 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
  18. 18.True or false: a candle usually has a microcontroller inside. (a) True (b) False
  19. 19.True or false: to open blinds at sunrise, use a gas sensor. (a) True (b) False
  20. 20.True or false: if the bulb is unscrewed, the circuit is open and no current flows. (a) True (b) False
  21. 21.🌐 Is a pencil sharpener an IoT device? (a) not an IoT device (b) an IoT device
  22. 22.🤖 if (distance < 30) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 24 cm. What happens?     (a) buzzer is silent (b) buzzer beeps
  23. 23.True or false: to fly kites in open fields is safe. (a) True (b) False
  24. 24.⏱️ A program says “wait 8500 ms”. How many seconds is that? =
  25. 25.🔌 Most metals are good … (a) insulators (b) batteries (c) conductors (d) magnets only
  26. 26.True or false: to run fans in empty rooms wastes electricity. (a) True (b) False
  27. 27.⏱️ How many milliseconds is a wait of 2.6 seconds?
  28. 28.🤖 if (temperature > 32) { show “Hot” } else if (temperature > 18) { show “Warm” } else { show “Cool” }
    The temperature is 36 °C. What is shown?     (a) Cool (b) Hot (c) Warm
  29. 29.⚙️ Which actuator would you use to open a gate to 90°? (a) a buzzer (b) a servo motor (c) a motor (d) an LED
  30. 30.🌈 In the resistor colour code, which number does black stand for?
  31. 31.⚠️ Is it safe to fly a kite near wires? (a) safe (b) not safe
  32. 32.🧮 Two equal 470 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
  33. 33.Which of these is measured in ohms (Ω)? (a) voltage (b) current (c) how much a part resists (d) power
  34. 34.True or false: the ammeter measures voltage. (a) True (b) False
  35. 35.🔋 How many 2 V cells must be joined in series to give 6 V?
  36. 36.Which drawing is the symbol for a junction? (a) a dot where wires meet (b) a circle with a cross (c) a plain rectangle (d) a circle with M inside
  37. 37.Which of these is a good habit? (a) accept every permission (b) post your live location (c) turn off unused gadgets (d) ignore update messages
  38. 38.🔋 5 identical 2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
  39. 39.🤖 if (moisture < 40) { pump ON } else { pump OFF }
    The soil moisture sensor reads 56 %. What happens?     (a) pump ON (b) pump OFF
  40. 40.🌈 A resistor has the colour bands red, blue, orange. What is its value in kilo-ohms (kΩ)? =

Answer key

  1. bigger
  2. 2
  3. it does not light
  4. False
  5. porch lamp OFF
  6. not safe
  7. less than either one
  8. log out of shared phones
  9. two or more cells joined
  10. anode (+)
  11. False
  12. post your live location
  13. True
  14. buzzer is silent
  15. False
  16. the else part
  17. V = I × R
  18. False
  19. False
  20. True
  21. not an IoT device
  22. buzzer beeps
  23. True
  24. 8.5
  25. conductors
  26. True
  27. 2600
  28. Hot
  29. a servo motor
  30. 0
  31. not safe
  32. 235
  33. how much a part resists
  34. False
  35. 3
  36. a dot where wires meet
  37. turn off unused gadgets
  38. 2
  39. pump OFF
  40. 26

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