Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 587 · 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 an insulator? (a) a brass key (b) a wooden stick (c) a steel coin (d) an iron nail
2. 2.🔌 A gap of dry air between two wires acts as … (a) a switch that is ON (b) a conductor (c) an insulator (d) a cell
3. 3.📶 Digital or analog: the room temperature? (a) analog (b) digital
4. 4.🌐 Is a plain table fan an IoT device? (a) not an IoT device (b) an IoT device
5. 5.True or false: on a cell, “the flat end” means the + (positive) end. (a) False (b) True
6. 6.🧾 One “unit” on an electricity bill is … (a) 1 ampere (b) 1 kilowatt-hour (kWh) (c) 1 watt (d) 1 volt
7. 7.True or false: to unplug idle chargers wastes electricity. (a) True (b) False
8. 8.True or false: a circle with V inside is the symbol for a battery. (a) False (b) True
9. 9.🔌 Is a steel coin a conductor or an insulator? (a) a conductor (b) an insulator
10. 10.⚠️ Is it safe to use small battery cells? (a) safe (b) not safe
11. 11.Which of these is measured in amperes (A)? (a) how much a part resists (b) current (c) resistance (d) voltage
12. 12.🔍 Which is the odd one out? (a) a woollen thread (b) a copper wire (c) a cotton thread (d) a rubber band
13. 13.🔘 Switch A is on the main wire next to the cell and the bulb; then the wire splits into two side-by-side paths, one with switch B and one with switch C. A is ON, B is OFF and C is OFF. Does the bulb glow? (a) No (b) Yes
14. 14.⚡ Power tells us … (a) energy used each second (b) the size of a cell (c) the colour of light (d) the length of a wire
15. 15.🔁 count = 0
    repeat 2 times { count = count + 4 }
    What is count at the end?
16. 16.🔋 On a cell, does “the flat end” mean the + end or the − end? (a) + (positive) (b) − (negative)
17. 17.🔘 When a switch is ON, the circuit is … (a) cut (b) broken (c) open (d) closed
18. 18.⏱️ loop forever { LED ON; wait 200 ms; LED OFF; wait 800 ms }
    How many times does the LED blink in 6 seconds?
19. 19.🔁 What does “count = count + 1” do? (a) prints 1 (b) takes 1 away (c) adds 1 to count (d) sets count to 1
20. 20.💡 4 identical bulbs are joined in series with a 10 V battery (ideal wires). How many volts does each bulb get? =
21. 21.✏️ In a circuit diagram, which part is drawn as two or more cell symbols? (a) cell (b) battery (c) switch (d) motor
22. 22.What does a motor do? (a) makes a beeping sound (b) boosts a small signal (c) turns a fan or wheels (d) blows if current is high
23. 23.⏱️ loop forever { LED ON; wait 100 ms; LED OFF; wait 950 ms }
    How many milliseconds does one blink (ON + OFF) take?
24. 24.🔍 An object is 170 cm from a distance sensor. Sound travels about 34 cm every millisecond. After how many milliseconds does the echo come back?
25. 25.💡 2 identical bulbs are joined in parallel (each on its own side-by-side path) with a battery and a closed switch on the main wire. Bulbs 1 and 2 are taken out of their holders. How many bulbs glow?
26. 26.⏱️ What does “wait 500 ms” do? (a) blinks 500 times (b) turns the LED off (c) waits 500 seconds (d) pauses for half a second
27. 27.Which of these is true of a parallel circuit? (a) one bulb out, all go out (b) a single current path (c) bulbs share the voltage (d) one out, the rest glow
28. 28.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 8 HIGH
    set pin 7 LOW
    set pin 8 HIGH
    set pin 7 LOW
    Is the LED ON or OFF at the end? (a) ON (b) OFF
29. 29.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 49 Ω resistor? (a) yellow-white-brown (b) green-white-black (c) white-yellow-black (d) yellow-white-black
30. 30.True or false: a resistor lets current go one way. (a) True (b) False
31. 31.Which job needs a soil moisture sensor? (a) spot someone walking in (b) make a parking alarm (c) water a dry plant (d) start a fan when hot
32. 32.🔁 repeat 4 times { repeat 4 times { beep } }
    How many beeps are there?
33. 33.💡 Why is house wiring done in parallel? (a) to make bulbs dim (b) to save copper only (c) so all go off together (d) each gets full voltage
34. 34.✏️ In a circuit diagram, which part is drawn as a circle with an X in it? (a) wire (b) LED (c) bulb (d) capacitor
35. 35.True or false: a torch mainly gives out heat. (a) True (b) False
36. 36.Which of these is safe? (a) throw cells in a fire (b) use small battery cells (c) touch a switch when wet (d) use mains for a project
37. 37.What does a fuse do? (a) limits the current (b) turns a fan or wheels (c) senses how bright it is (d) blows if current is high
38. 38.✏️ In a cell symbol, which line is the + terminal? (a) neither line (b) the shorter line (c) the longer line (d) both lines
39. 39.🔌 Which part of a screwdriver should an electrician hold? (a) the metal tip (b) the bare end (c) the steel shaft (d) the plastic handle
40. 40.True or false: “each gets the full volts” is true of a series circuit. (a) False (b) True

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