Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 323 · 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.💡 An LED (with its resistor) is on pin 7. All pins start LOW. The program runs once:
   set pin 8 LOW
   set pin 7 LOW
   set pin 8 LOW
   set pin 7 LOW
   Is the LED ON or OFF at the end? (a) ON (b) OFF
2. 2.🔌 Is a rubber eraser a conductor or an insulator? (a) an insulator (b) a conductor
3. 3.Which job needs a soil moisture sensor? (a) open blinds at sunrise (b) water a dry plant (c) warn of a gas leak (d) stop a robot near walls
4. 4.📏 How many amperes (A) is 1850 mA? =
5. 5.True or false: to fly kites in open fields is not safe. (a) True (b) False
6. 6.Which of these means the circuit is closed? (a) a cell is taken out (b) the switch is OFF (c) the switch is ON (d) the bulb is unscrewed
7. 7.🔋 3 identical 1.5 V cells are joined in series, but one of them is put in the wrong way round. What is the total voltage now (in volts)? =
8. 8.🔁 Is the circuit closed or open if a wire is cut? (a) closed (b) open
9. 9.🧩 Which part changes electrical energy into sound? (a) a diode (b) a buzzer (c) a resistor (d) a capacitor
10. 10.🧮 Two resistors in parallel give a total that is … (a) their sum (b) less than either one (c) always zero (d) more than either one
11. 11.True or false: a laptop needs much more power. (a) True (b) False
12. 12.🔐 Is it a good or a risky habit to share the Wi-Fi key? (a) risky habit (b) good habit
13. 13.🔢 To plan an electronics project, what comes right after “list inputs and outputs”? (a) build it with an adult (b) test it and fix it (c) draw the circuit diagram (d) pick a problem to solve
14. 14.📏 How many milliamperes (mA) is 1.18 A?
15. 15.True or false: to use small battery cells is not safe. (a) False (b) True
16. 16.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 7200 Ω resistor? (a) red-violet-red (b) violet-red-brown (c) violet-red-red (d) violet-red-orange
17. 17.🤖 if (temperature > 37) { show “Hot” } else if (temperature > 21) { show “Warm” } else { show “Cool” }
    The temperature is 17 °C. What is shown? (a) Warm (b) Cool (c) Hot
18. 18.True or false: if all wires are joined, the circuit is closed and current flows. (a) False (b) True
19. 19.✏️ In a circuit diagram, which part is drawn as a straight line? (a) motor (b) LED (c) battery (d) wire
20. 20.⚡ A home appliance on the 230 V mains takes 4 A. What is its power (in watts)?
21. 21.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they get dimmer (b) they keep glowing (c) they explode (d) they all go out
22. 22.🔌 Is a dry cork a conductor or an insulator? (a) a conductor (b) an insulator
23. 23.💡 Does it save or waste electricity to switch off empty rooms? (a) wastes electricity (b) saves electricity
24. 24.🔺 A 7.5 V supply is joined across a 300 Ω resistor. What current flows (in milliamperes, mA)?
25. 25.📶 On a 5 V board, a pin set HIGH gives about … (a) 5 V (b) 0 V (c) 50 V (d) 230 V
26. 26.True or false: a circle with V inside is the symbol for a switch. (a) False (b) True
27. 27.Which of these is a good habit? (a) share camera links (b) accept every permission (c) change default passwords (d) ignore update messages
28. 28.Which job needs a distance sensor? (a) switch on with a clap (b) make a parking alarm (c) open blinds at sunrise (d) spot someone walking in
29. 29.🔋 Does a computer give electricity or use electricity? (a) gives electricity (b) uses electricity
30. 30.🔍 Which is the odd one out? (a) poke things in a socket (b) touch a switch when wet (c) open a phone charger (d) take cells out after use
31. 31.⚡ A device works on 24 V and takes 0.2 A. What is its power (in watts)? =
32. 32.🔍 Which is the odd one out? (a) install software updates (b) cover unused cameras (c) keep factory passwords (d) set a strong password
33. 33.🌐 Each reading a sensor sends is 25 bytes. How many bytes do 40 readings take?
34. 34.⚡ What does a night lamp mainly change electricity into? (a) heat (b) movement (c) light (d) sound
35. 35.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
36. 36.🧮 Resistors of 50 Ω and 68 Ω are joined in series. What is the total resistance (in ohms)?
37. 37.🔁 count = 9
    repeat 10 times { count = count + 5 }
    What is count at the end?
38. 38.🔁 x = 3
    repeat 5 times { x = x × 2 }
    What is x at the end?
39. 39.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
40. 40.🔐 Which is the strongest password for a home smart camera? (a) admin (b) 123456 (c) Tiger#Lamp42!Moon (d) password

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