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Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 810 · 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.⏱️ What does “wait 500 ms” do? (a) turns the LED off (b) pauses for half a second (c) waits 500 seconds (d) blinks 500 times
  2. 2.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is OFF, B is OFF and C is ON. Does the bulb glow? (a) No (b) Yes
  3. 3.True or false: “a single current path” is true of a parallel circuit. (a) True (b) False
  4. 4.Which of these is a risky habit? (a) keep factory passwords (b) read app permissions (c) set a strong password (d) log out of shared phones
  5. 5.📶 Digital or analog: a tilt switch: on or off? (a) analog (b) digital
  6. 6.🔁 Is the circuit closed or open if a wire is cut? (a) open (b) closed
  7. 7.⚠️ Is it safe to take cells out after use? (a) safe (b) not safe
  8. 8.🔁 count = 0
    while (count < 14) { count = count + 2 }
    How many times does the loop run?
  9. 9.🧮 Four equal 200 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
  10. 10.🔁 What does “count = count + 1” do? (a) adds 1 to count (b) takes 1 away (c) prints 1 (d) sets count to 1
  11. 11.True or false: to set the AC to 24 °C saves electricity. (a) True (b) False
  12. 12.🧮 Two resistors in parallel give a total that is … (a) their sum (b) always zero (c) more than either one (d) less than either one
  13. 13.🧩 Which component has coloured bands? (a) motor (b) resistor (c) diode (d) capacitor
  14. 14.True or false: a buzzer lets current go one way. (a) False (b) True
  15. 15.🌈 A resistor has the colour bands orange, black, yellow. What is its value in kilo-ohms (kΩ)? =
  16. 16.🔺 A 16 V supply is joined across a 400 Ω resistor. What current flows (in milliamperes, mA)?
  17. 17.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they explode (b) they all go out (c) they keep glowing (d) they get dimmer
  18. 18.What does the cloud server do? (a) measures the real world (b) stores data online (c) shows data to you (d) reads values, decides
  19. 19.📶 Digital or analog: how bright a room is? (a) digital (b) analog
  20. 20.🌐 In an IoT system, which part measures the real world? (a) microcontroller (b) actuator (c) sensor (d) Wi-Fi
  21. 21.True or false: many long-short pairs is the symbol for a battery. (a) False (b) True
  22. 22.🔘 A cell and a bulb are joined to 2 side-by-side paths with one switch on each path — A and B (parallel). A is OFF and B is OFF. Does the bulb glow? (a) No (b) Yes
  23. 23.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 62000 Ω resistor? (a) red-blue-orange (b) blue-red-yellow (c) blue-red-orange (d) blue-red-red
  24. 24.🔌 Is a paper strip a conductor or an insulator? (a) a conductor (b) an insulator
  25. 25.🔁 What does a variable do in a program? (a) stores a value (b) joins two wires (c) measures light (d) blinks an LED
  26. 26.🧭 Which part of a microcontroller board shows the board is on? (a) the main chip (b) the power LED (c) the USB port (d) the pins
  27. 27.🤖 “if (A AND B)” is true when … (a) only A is true (b) both are false (c) only B is true (d) both A and B are true
  28. 28.⚡ Power tells us … (a) energy used each second (b) the length of a wire (c) the size of a cell (d) the colour of light
  29. 29.🧮 A 33 Ω resistor is joined in series with two equal 50 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
  30. 30.💡 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)?
  31. 31.💡 Why does an LED need a resistor in series? (a) to limit the current (b) to change its colour (c) to make it brighter (d) to store charge
  32. 32.🔍 Which is the odd one out? (a) stay away from pylons (b) throw cells in a fire (c) use mains for a project (d) climb an electric pole
  33. 33.True or false: to use a cable with cuts is not safe. (a) False (b) True
  34. 34.Which of these saves electricity? (a) run fans in empty rooms (b) leave the TV on standby (c) set the AC to 24 °C (d) iron one shirt at a time
  35. 35.💡 3 identical bulbs are in parallel and each one takes 1.5 A. What total current (in amperes) comes from the battery? =
  36. 36.🤖 Does a bicycle bell usually have a microcontroller inside? (a) Yes (b) No
  37. 37.True or false: to start a fan when hot, use a sound sensor. (a) True (b) False
  38. 38.💡 2 identical bulbs are in parallel and each one takes 0.5 A. What total current (in amperes) comes from the battery? =
  39. 39.True or false: to switch off empty rooms wastes electricity. (a) True (b) False
  40. 40.⚠️ Is it safe to use small battery cells? (a) not safe (b) safe

Answer key

  1. pauses for half a second
  2. No
  3. False
  4. keep factory passwords
  5. digital
  6. open
  7. safe
  8. 7
  9. 50
  10. adds 1 to count
  11. True
  12. less than either one
  13. resistor
  14. False
  15. 300
  16. 40
  17. they keep glowing
  18. stores data online
  19. analog
  20. sensor
  21. True
  22. No
  23. blue-red-orange
  24. an insulator
  25. stores a value
  26. the power LED
  27. both A and B are true
  28. energy used each second
  29. 58
  30. 5
  31. to limit the current
  32. stay away from pylons
  33. True
  34. set the AC to 24 °C
  35. 4.5
  36. No
  37. False
  38. 1
  39. False
  40. safe

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