Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 49 · 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.🔌 Most metals are good … (a) batteries (b) magnets only (c) insulators (d) conductors
2. 2.True or false: current is measured in watts (W). (a) False (b) True
3. 3.⚠️ Is it safe to stay away from pylons? (a) not safe (b) safe
4. 4.🔋 Does a generator give electricity or use electricity? (a) gives electricity (b) uses electricity
5. 5.🔐 Is it a good or a risky habit to share the Wi-Fi key? (a) risky habit (b) good habit
6. 6.🧮 Two equal 1000 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
7. 7.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the battery (b) the output (c) the process (d) the input
8. 8.Which of these is an IoT device? (a) a paper calendar (b) a Wi-Fi smart plug (c) a battery torch (d) a plain table fan
9. 9.Which of these mainly makes sound? (a) a traffic signal (b) a ceiling fan (c) a street light (d) a siren
10. 10.Which of these is measured in amperes (A)? (a) current (b) energy used each second (c) voltage (d) how much a part resists
11. 11.Which of these is an output? (a) a motion sensor (b) a keypad (c) an LED (d) a turning knob
12. 12.🔁 count = 5
    while (count < 20) { count = count + 5 }
    How many times does the loop run?
13. 13.🔍 Which is the odd one out? (a) set a strong password (b) install software updates (c) share the Wi-Fi key (d) change default passwords
14. 14.🔁 Is the circuit closed or open if all wires are joined? (a) closed (b) open
15. 15.🧮 Two resistors in parallel give a total that is … (a) more than either one (b) less than either one (c) always zero (d) their sum
16. 16.True or false: to use LED lamps wastes electricity. (a) False (b) True
17. 17.🔁 count = 0
    repeat 10 times { count = count + 2 }
    What is count at the end?
18. 18.🔍 Which is the odd one out? (a) a wooden stick (b) a graphite rod (c) a brass key (d) a metal paper clip
19. 19.⏱️ repeat 8 times { buzzer ON; wait 700 ms; buzzer OFF; wait 1000 ms }
    How many milliseconds does this take in all?
20. 20.📏 How many amperes (A) is 420 mA? =
21. 21.True or false: if a wire is cut, the circuit is open and no current flows. (a) False (b) True
22. 22.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) − (negative) (b) + (positive)
23. 23.🔋 Does a cell give electricity or use electricity? (a) gives electricity (b) uses electricity
24. 24.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 7 LOW
    set pin 7 LOW
    set pin 8 LOW
    set pin 8 LOW
    Is the LED ON or OFF at the end? (a) OFF (b) ON
25. 25.🤖 if (distance < 30) { buzzer beeps } else { buzzer is silent }
    The distance sensor reads 29 cm. What happens? (a) buzzer is silent (b) buzzer beeps
26. 26.🤖 if (light < 300 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 200 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
27. 27.⏱️ repeat 6 times { buzzer ON; wait 300 ms; buzzer OFF; wait 100 ms }
    How many milliseconds does this take in all?
28. 28.📏 How many milliamperes (mA) make 1 ampere? (a) 60 (b) 1000 (c) 100 (d) 10
29. 29.🔋 6 identical 1.2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
30. 30.💡 A battery lights 4 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) the same (b) dimmer (c) brighter
31. 31.What does a toggle switch do? (a) closes near a magnet (b) springs back when let go (c) flips up or down (d) slides side to side
32. 32.💡 5 identical bulbs are joined in series with a 12.5 V battery (ideal wires). How many volts does each bulb get? =
33. 33.⚠️ Is it safe to climb an electric pole? (a) not safe (b) safe
34. 34.🔺 A 12 V supply is joined across a 12 Ω resistor. What current flows (in amperes)? =
35. 35.💡 A blue LED uses 3 V and should get 25 mA. It runs from a 5 V supply. What resistor (in ohms) is needed in series?
36. 36.Which of these is true of a parallel circuit? (a) one bulb out, all go out (b) bulbs share the voltage (c) many paths for current (d) a single current path
37. 37.🗺️ In an input → process → output plan, is “an LED lights up” the input, the process or the output? (a) output (b) input (c) process
38. 38.🌈 A resistor has the colour bands grey, yellow, red. What is its value in kilo-ohms (kΩ)? =
39. 39.True or false: a circle with M inside is the symbol for a cell. (a) False (b) True
40. 40.📏 How many kilowatts (kW) is 3050 W? =

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