Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 749 · 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.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) the else part (b) neither part (c) the if part (d) both parts
2. 2.🌐 In an IoT system, which part measures the real world? (a) actuator (b) phone app (c) sensor (d) microcontroller
3. 3.True or false: to stay away from pylons is not safe. (a) True (b) False
4. 4.💡 2 identical bulbs are joined in series with a battery and a closed switch on the main wire. All the bulbs are in place. How many bulbs glow?
5. 5.🧩 Which component glows using little power? (a) capacitor (b) LED (c) buzzer (d) resistor
6. 6.⚠️ Is it safe to throw cells in a fire? (a) safe (b) not safe
7. 7.🔘 Which kind of switch closes when tipped over? (a) a slide switch (b) a tilt switch (c) a reed switch (d) a toggle switch
8. 8.🔍 Which is the odd one out? (a) count button presses (b) a soil moisture reading (c) compare with a limit (d) check if temp > 30
9. 9.📏 Voltmeter or ammeter: which one measures current? (a) voltmeter (b) ammeter
10. 10.🔐 Privacy for a smart device means controlling … (a) how loud it beeps (b) its colour (c) who can see your data (d) its battery size
11. 11.Which of these is a good habit? (a) tap unknown app links (b) accept every permission (c) keep factory passwords (d) change default passwords
12. 12.Which job needs a motor? (a) beep an alarm (b) spin a robot’s wheels (c) turn to an exact angle (d) open a gate to 90°
13. 13.🔍 For a microcontroller, is a sensor an input or an output? (a) a power source (b) a fuse (c) an output (d) an input
14. 14.🔢 To run one loop of a plant-watering program, which comes first: “wait a few seconds” or “read the soil sensor”? (a) wait a few seconds (b) read the soil sensor
15. 15.💡 Why does an LED need a resistor in series? (a) to change its colour (b) to limit the current (c) to make it brighter (d) to store charge
16. 16.🔺 A current of 20 mA flows through a 100 Ω resistor. What is the voltage across it (in volts)? =
17. 17.🔐 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
18. 18.Which drawing is the symbol for an LED? (a) a circle with A inside (b) two or more cell symbols (c) triangle, bar and arrows (d) a circle with V inside
19. 19.💡 4 identical bulbs are joined in series with a battery and a closed switch on the main wire. Bulb 1 is taken out of its holder. How many bulbs glow?
20. 20.📏 How many watts (W) is 1.7 kW?
21. 21.🔋 On a cell, does “the longer symbol line” mean the + end or the − end? (a) − (negative) (b) + (positive)
22. 22.True or false: “own switch for each bulb” is true of a series circuit. (a) False (b) True
23. 23.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the process (b) the battery (c) the output (d) the input
24. 24.⚡ What does an electric iron mainly change electricity into? (a) light (b) sound (c) heat (d) movement
25. 25.📶 Digital or analog: a door: open or shut? (a) analog (b) digital
26. 26.⚡ What does an electric toy car mainly change electricity into? (a) light (b) heat (c) movement (d) sound
27. 27.🗺️ Before building a project, what should you write down first? (a) the box colour (b) inputs and outputs (c) the final price (d) nothing at all
28. 28.🔋 2 identical 1.2 V cells are joined in series (+ of one cell to − of the next). What is the total voltage (in volts)? =
29. 29.🤖 How does a new program get onto a microcontroller board? (a) sent by sound (b) drawn with a pen (c) uploaded over USB (d) typed on the chip
30. 30.True or false: a potentiometer is a resistance knob. (a) False (b) True
31. 31.🔺 In the V-I-R triangle, how do we find V? (a) V = R ÷ I (b) V = I + R (c) V = I × R (d) V = I ÷ R
32. 32.⚡ A home appliance on the 230 V mains takes 10 A. What is its power (in watts)?
33. 33.📶 Digital or analog: how bright a room is? (a) analog (b) digital
34. 34.🔌 Which metal is used for most electric wires at home? (a) glass (b) rubber (c) copper (d) plastic
35. 35.🧩 Which component turns a fan or wheels? (a) motor (b) buzzer (c) capacitor (d) LED
36. 36.True or false: if the bulb is unscrewed, the circuit is closed and current flows. (a) False (b) True
37. 37.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 5200 Ω resistor? (a) red-green-red (b) green-red-orange (c) green-red-brown (d) green-red-red
38. 38.💡 Why is house wiring done in parallel? (a) to save copper only (b) so all go off together (c) each gets full voltage (d) to make bulbs dim
39. 39.True or false: a ceiling fan mainly makes movement. (a) False (b) True
40. 40.🔋 2 identical 3 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =

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