Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 521 · 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.True or false: to use a cable with cuts is not safe. (a) False (b) True
2. 2.🔁 count = 4
   repeat 6 times { count = count + 3 }
   What is count at the end?
3. 3.True or false: on a cell, “the longer symbol line” means the + (positive) end. (a) True (b) False
4. 4.🔋 Does a washing machine give electricity or use electricity? (a) uses electricity (b) gives electricity
5. 5.🔋 What is a battery? (a) a kind of bulb (b) a switch with a lid (c) two or more cells joined (d) one single wire
6. 6.⚡ Which formula gives electric power? (a) P = V × I (b) P = V + I (c) P = I ÷ V (d) P = V ÷ I
7. 7.📏 How many ohms (Ω) is 6.7 kΩ?
8. 8.🧮 Adding another resistor in series makes the total resistance … (a) zero (b) stay the same (c) smaller (d) bigger
9. 9.🧩 Which part changes electrical energy into movement? (a) a fuse (b) a resistor (c) an LED (d) a motor
10. 10.⚡ 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
11. 11.📏 Voltmeter or ammeter: which one measures voltage? (a) ammeter (b) voltmeter
12. 12.🔍 Which sensor would you use to close a window in rain? (a) a rain sensor (b) a motion sensor (c) a temperature sensor (d) a sound sensor
13. 13.🧮 A 0.7 V battery is joined to 3 Ω and 4 Ω resistors in series. What current flows (in amperes)? =
14. 14.What does the cloud server do? (a) reads values, decides (b) measures the real world (c) carries the data (d) stores data online
15. 15.💡 2 identical bulbs are joined in series with a 5 V battery (ideal wires). How many volts does each bulb get? =
16. 16.True or false: on a cell, “the flat end” means the + (positive) end. (a) False (b) True
17. 17.🔍 Which is the odd one out? (a) a temperature reading (b) compare with a limit (c) a soil moisture reading (d) a button press
18. 18.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the else part (b) the if part (c) neither part (d) both parts
19. 19.⏱️ How many milliseconds are in 1 second? (a) 1000 (b) 10 (c) 100 (d) 60
20. 20.🧩 Which part changes electrical energy into sound? (a) a capacitor (b) a resistor (c) a diode (d) a buzzer
21. 21.🌈 A resistor has the colour bands white, violet, yellow. What is its value in kilo-ohms (kΩ)? =
22. 22.💡 A red LED (it uses 2 V) is joined with a 150 Ω resistor to a 3.5 V supply. What current flows (in mA)?
23. 23.What does a motor do? (a) makes things spin (b) senses how hot it is (c) smooths a wobbly supply (d) makes a beeping sound
24. 24.🧩 Which component stores a little charge? (a) LDR (b) capacitor (c) transistor (d) potentiometer
25. 25.True or false: “a soil moisture reading” is the output. (a) False (b) True
26. 26.🔗 Series or parallel circuit: “bulbs share the voltage”? (a) parallel (b) series
27. 27.🔁 total = 0
    for i = 1 to 5 { total = total + i }
    What is total at the end?
28. 28.Which of these is a risky habit? (a) log out of shared phones (b) set up with a parent (c) turn off unused gadgets (d) keep factory passwords
29. 29.🗺️ In an input → process → output plan, is “count button presses” the input, the process or the output? (a) input (b) output (c) process
30. 30.🤖 if (light < 500) { lamp ON } else { lamp OFF }
    The light sensor reads 635. What happens? (a) lamp OFF (b) lamp ON
31. 31.🤖 Where does the board keep its program when the power is off? (a) flash memory (b) the power LED (c) the USB cable (d) the resistor
32. 32.🧭 Which part of a microcontroller board runs the program? (a) the pins (b) the USB port (c) the reset button (d) the main chip
33. 33.Which of these is not an IoT device? (a) a fitness band with app (b) a Wi-Fi smart plug (c) a smart energy meter (d) a wind-up clock
34. 34.💡 Does it save or waste electricity to switch off empty rooms? (a) saves electricity (b) wastes electricity
35. 35.🔐 Privacy for a smart device means controlling … (a) its colour (b) how loud it beeps (c) its battery size (d) who can see your data
36. 36.📏 How many watts (W) is 4.3 kW?
37. 37.True or false: on an LED, the longer leg is the cathode (−). (a) True (b) False
38. 38.✏️ In a circuit diagram, which part is drawn as a long and a short line? (a) capacitor (b) LED (c) cell (d) junction
39. 39.🤖 if (moisture < 30) { pump ON } else { pump OFF }
    The soil moisture sensor reads 35 %. What happens? (a) pump OFF (b) pump ON
40. 40.🔺 A 7.5 V supply is joined across a 5 Ω resistor. What current flows (in amperes)? =

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