Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 453 · 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.🔘 A cell and a bulb are joined to 4 side-by-side paths with one switch on each path — A, B, C and D (parallel). A is ON, B is ON, C is OFF and D is OFF. Does the bulb glow? (a) No (b) Yes
2. 2.💡 4 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 4 is taken out of its holder. How many bulbs glow?
3. 3.📏 How many milliamperes (mA) make 1 ampere? (a) 10 (b) 1000 (c) 100 (d) 60
4. 4.📶 A pin set LOW gives about … (a) 9 V (b) 1.5 V (c) 5 V (d) 0 V
5. 5.Which drawing is the symbol for a capacitor? (a) two equal parallel lines (b) a small empty box (c) triangle, bar and arrows (d) one tall, one short bar
6. 6.🔍 Which is the odd one out? (a) fly kites in open fields (b) touch a switch when wet (c) poke things in a socket (d) use mains for a project
7. 7.True or false: a table fan mainly makes sound. (a) True (b) False
8. 8.Which of these means the circuit is open? (a) the loop is complete (b) a cell is taken out (c) all wires are joined (d) the switch is ON
9. 9.🔦 A circuit has a new cell, a good bulb and a switch that is ON. All the wires are firmly joined. A gap in one wire is bridged by a wooden stick. Does the bulb glow? (a) No (b) Yes
10. 10.🔺 In the V-I-R triangle, how do we find V? (a) V = I ÷ R (b) V = I + R (c) V = I × R (d) V = R ÷ I
11. 11.🔺 An 18.8 V supply is joined across a 470 Ω resistor. What current flows (in milliamperes, mA)?
12. 12.🧭 Which part of a microcontroller board restarts the program? (a) the reset button (b) the USB port (c) the pins (d) the main chip
13. 13.🔍 Which is the odd one out? (a) the pump turns on (b) count button presses (c) compare with a limit (d) check if temp > 30
14. 14.Which of these means the circuit is open? (a) all wires are joined (b) the switch is ON (c) a wire is cut (d) the loop is complete
15. 15.Which job needs a sound sensor? (a) spot someone walking in (b) switch on lamps at dusk (c) switch on with a clap (d) open blinds at sunrise
16. 16.Which of these is a conductor? (a) a cotton thread (b) a plastic straw (c) aluminium foil (d) a plastic ruler
17. 17.💡 A blue LED uses 3 V and should get 25 mA. It runs from a 12 V supply. What resistor (in ohms) is needed in series?
18. 18.🔋 What should you do with used-up cells? (a) cut them open (b) throw them in a fire (c) bury them in soil (d) give them for recycling
19. 19.🔋 On a cell, does “the end with a bump” mean the + end or the − end? (a) − (negative) (b) + (positive)
20. 20.🌈 A resistor has the colour bands grey, orange, orange. What is its value in kilo-ohms (kΩ)? =
21. 21.🤖 if (light < 400 AND motion) { porch lamp ON } else { porch lamp OFF }
    The light reading is 110 and motion is not detected (false). What happens? (a) porch lamp OFF (b) porch lamp ON
22. 22.🌐 Is a pencil sharpener an IoT device? (a) an IoT device (b) not an IoT device
23. 23.💡 A battery lights 3 identical bulbs joined in series. One more identical bulb is added in series. How do the bulbs glow now? (a) brighter (b) the same (c) dimmer
24. 24.Which job needs an LED? (a) beep an alarm (b) spin a robot’s wheels (c) show a status light (d) turn to an exact angle
25. 25.True or false: if the switch is ON, the circuit is open and no current flows. (a) True (b) False
26. 26.🧮 Two equal 1000 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
27. 27.Which of these is measured in amperes (A)? (a) resistance (b) how much a part resists (c) the push of a cell (d) the flow of charge
28. 28.🔋 Does a cell give electricity or use electricity? (a) uses electricity (b) gives electricity
29. 29.Which of these is a conductor? (a) a rubber band (b) a dry cork (c) a metal paper clip (d) a paper strip
30. 30.🔐 A smart speaker is always listening for its wake word. What is a sensible habit? (a) let strangers use it (b) mute it when not in use (c) tell it your passwords (d) put it in the bathroom
31. 31.Which of these is an IoT device? (a) a wind-up clock (b) a pencil sharpener (c) a battery torch (d) a Wi-Fi smart plug
32. 32.🤖 Does a candle usually have a microcontroller inside? (a) Yes (b) No
33. 33.💡 In a parallel circuit, one bulb breaks. What happens to the others? (a) they all go out (b) they explode (c) they keep glowing (d) they get dimmer
34. 34.🔁 Is the circuit closed or open if the loop is complete? (a) open (b) closed
35. 35.Which of these means the circuit is open? (a) all wires are joined (b) the switch is ON (c) the loop is complete (d) a wire has come loose
36. 36.Which job needs a temperature sensor? (a) water a dry plant (b) measure classroom noise (c) make a parking alarm (d) start a fan when hot
37. 37.True or false: “many paths for current” is true of a parallel circuit. (a) False (b) True
38. 38.🔋 Does a mobile phone give electricity or use electricity? (a) gives electricity (b) uses electricity
39. 39.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) neither part (b) the if part (c) the else part (d) both parts
40. 40.🤖 Microcontroller or laptop: which one runs one small program? (a) microcontroller (b) laptop

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