Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 241 · 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.Which of these is not safe? (a) take cells out after use (b) dry your hands first (c) use small battery cells (d) touch a fallen wire
2. 2.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a cotton thread across the gap. Does the bulb glow? (a) Yes (b) No
3. 3.🔍 Which sensor would you use to make a parking alarm? (a) a sound sensor (b) a gas sensor (c) a temperature sensor (d) a distance sensor
4. 4.🔁 What does a variable do in a program? (a) blinks an LED (b) stores a value (c) joins two wires (d) measures light
5. 5.🔗 Series or parallel circuit: “one bulb out, all go out”? (a) series (b) parallel
6. 6.Which of these mainly makes sound? (a) a rice cooker (b) a toaster (c) an electric kettle (d) a school bell
7. 7.🔋 On a cell, does “the shorter symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
8. 8.Which of these is an insulator? (a) a steel coin (b) a brass key (c) a paper strip (d) aluminium foil
9. 9.🔁 total = 0
   for i = 1 to 3 { total = total + i }
   What is total at the end?
10. 10.⚡ A home appliance on the 230 V mains takes 1 A. What is its power (in watts)?
11. 11.Which of these is safe? (a) throw cells in a fire (b) touch a fallen wire (c) fly a kite near wires (d) keep drinks far away
12. 12.🔦 A tester circuit has a new cell, a good bulb and wires with a gap between two clips. We put a steel spoon across the gap. Does the bulb glow? (a) No (b) Yes
13. 13.✏️ Why do engineers draw circuits with symbols? (a) quick and clear for all (b) to hide the circuit (c) symbols are heavier (d) to make it colourful
14. 14.Which of these has no microcontroller inside? (a) a candle (b) a microwave oven (c) a digital thermometer (d) a smart watch
15. 15.🧮 Two equal 470 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
16. 16.Which job needs an LED? (a) show a status light (b) move water to plants (c) show the temperature (d) turn to an exact angle
17. 17.🔺 The voltage stays the same and the resistance gets bigger. The current … (a) stays the same (b) gets bigger (c) becomes zero (d) gets smaller
18. 18.⚠️ Is it safe to fly kites in open fields? (a) safe (b) not safe
19. 19.🏠 Which is a smart-home example? (a) a candle in a jar (b) a printed map (c) lights on from an app (d) a hand fan
20. 20.🤖 Where does the board keep its program when the power is off? (a) the resistor (b) the USB cable (c) the power LED (d) flash memory
21. 21.True or false: one tall, one short bar is the symbol for a cell. (a) False (b) True
22. 22.💡 2 identical bulbs are joined in series with a 2 V battery (ideal wires). How many volts does each bulb get? =
23. 23.True or false: on a cell, “usually the red wire” means the + (positive) end. (a) False (b) True
24. 24.True or false: the voltmeter measures voltage. (a) True (b) False
25. 25.⚠️ Is it safe to throw cells in a fire? (a) safe (b) not safe
26. 26.Which of these is a risky habit? (a) change default passwords (b) cover unused cameras (c) share camera links (d) log out of shared phones
27. 27.🔍 A distance sensor sends a sound pulse and hears the echo 12 ms later. Sound travels about 34 cm every millisecond. How far away is the object (in cm)?
28. 28.🔍 Which is the odd one out? (a) change default passwords (b) set up with a parent (c) post your live location (d) share only needed data
29. 29.True or false: on a cell, “usually the red wire” means the − (negative) end. (a) False (b) True
30. 30.🔐 Is it a good or a risky habit to read app permissions? (a) good habit (b) risky habit
31. 31.Which of these is measured in ohms (Ω)? (a) how much a part resists (b) voltage (c) current (d) energy used each second
32. 32.True or false: the voltmeter is joined across a part. (a) True (b) False
33. 33.🤖 if (temperature > 25) { fan ON } else { fan OFF }
    The temperature sensor reads 18 °C. What happens? (a) fan ON (b) fan OFF
34. 34.Which of these means the circuit is closed? (a) all wires are joined (b) a wire is cut (c) a cell is taken out (d) a wire has come loose
35. 35.🔍 Which is the odd one out? (a) a paper strip (b) a glass marble (c) a rubber band (d) a brass key
36. 36.🔍 Which is the odd one out? (a) touch a switch when wet (b) use mains for a project (c) touch a fallen wire (d) use small battery cells
37. 37.🔍 Which is the odd one out? (a) a water pump (b) a sound sensor (c) a buzzer (d) a motor
38. 38.True or false: to touch a fallen wire is not safe. (a) True (b) False
39. 39.True or false: a diode lets current go one way. (a) False (b) True
40. 40.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 360 and motion is detected (true). What happens? (a) porch lamp OFF (b) porch lamp ON

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