Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 760 · 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.🔋 Cells joined + to − in a row (series) give … (a) a smaller voltage (b) no voltage (c) a bigger voltage (d) the same voltage
2. 2.🤖 Microcontroller or laptop: which one runs many apps at once? (a) microcontroller (b) laptop
3. 3.🔋 How many 3 V cells must be joined in series to give 9 V?
4. 4.🔘 What does a switch do in a circuit? (a) makes electricity (b) changes the voltage (c) stores current (d) opens or closes the loop
5. 5.Which drawing is the symbol for a motor? (a) a long and a short line (b) a circle with M inside (c) two or more cell symbols (d) a line lifted at a gap
6. 6.True or false: to keep an incubator warm, use a motion sensor. (a) False (b) True
7. 7.⚡ What does a mixer grinder mainly change electricity into? (a) heat (b) light (c) sound (d) movement
8. 8.What does a tilt switch do? (a) flips up or down (b) closes when tipped over (c) stays where you flip it (d) works only while pressed
9. 9.💡 A battery lights 4 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) brighter (c) dimmer
10. 10.Which of these is true of a parallel circuit? (a) a break stops every bulb (b) a single current path (c) own switch for each bulb (d) one bulb out, all go out
11. 11.True or false: if all wires are joined, the circuit is closed and current flows. (a) True (b) False
12. 12.Which of these wastes electricity? (a) switch off empty rooms (b) close the fridge quickly (c) leave the TV on standby (d) unplug idle chargers
13. 13.✏️ In a circuit diagram, which part is drawn as a small empty box? (a) LED (b) battery (c) ammeter (d) resistor
14. 14.💡 A blue LED uses 3 V and should get 10 mA. It runs from a 5 V supply. What resistor (in ohms) is needed in series?
15. 15.Which drawing is the symbol for a bulb? (a) many long-short pairs (b) a circle with V inside (c) a circle with a cross (d) a line lifted at a gap
16. 16.🔁 What does “count = count + 1” do? (a) sets count to 1 (b) adds 1 to count (c) prints 1 (d) takes 1 away
17. 17.📏 How many milliamperes (mA) is 2.44 A?
18. 18.True or false: on a cell, “the shorter symbol line” means the + (positive) end. (a) False (b) True
19. 19.Which of these is true of a parallel circuit? (a) a break stops every bulb (b) a single current path (c) one out, the rest glow (d) one bulb out, all go out
20. 20.⚡ A home appliance on the 230 V mains takes 8 A. What is its power (in watts)?
21. 21.Which of these is an input? (a) an LED (b) a small display (c) a turning knob (d) a servo motor
22. 22.🧾 A 100 W filament bulb is swapped for a 15 W LED lamp that gives about the same light. Both would run for 2 hours. How many watt-hours (Wh) are saved?
23. 23.🌐 Each reading a sensor sends is 20 bytes. How many bytes do 30 readings take?
24. 24.🗺️ In an input → process → output plan, is “count button presses” the input, the process or the output? (a) output (b) input (c) process
25. 25.🔁 total = 0
    for i = 1 to 4 { total = total + i }
    What is total at the end?
26. 26.🔍 For a microcontroller, is a sensor an input or an output? (a) a fuse (b) a power source (c) an input (d) an output
27. 27.🤖 Microcontroller or laptop: which one runs one small program? (a) laptop (b) microcontroller
28. 28.Which of these is the process? (a) count button presses (b) an LED lights up (c) a motion sensor signal (d) a button press
29. 29.🔋 A 3 V battery and two 1.5 V cells are joined in series, all facing the same way. What is the total voltage (in volts)? =
30. 30.🔢 To get a sensor reading onto a phone, what comes right after “the sensor measures”? (a) it is sent by Wi-Fi (b) the app shows it (c) the board reads it (d) the cloud stores it
31. 31.🔍 Which is the odd one out? (a) a glass marble (b) a plastic straw (c) a brass key (d) a dry cork
32. 32.Which of these is true of a series circuit? (a) a break stops every bulb (b) one out, the rest glow (c) many paths for current (d) used in house wiring
33. 33.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
34. 34.🔘 Which kind of switch stays where you flip it? (a) a tilt switch (b) a toggle switch (c) a push button (d) a slide switch
35. 35.⚡ A home appliance on the 230 V mains takes 1 A. What is its power (in watts)?
36. 36.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
37. 37.Which of these is a good habit? (a) ignore update messages (b) keep factory passwords (c) set a strong password (d) accept every permission
38. 38.🌈 A resistor has the colour bands yellow, black, red. What is its value (in ohms)?
39. 39.True or false: the voltmeter is joined in series. (a) False (b) True
40. 40.✏️ In a circuit diagram, wires are usually drawn as … (a) little stars (b) dotted circles (c) straight lines (d) wavy lines

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