Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 922 · 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 saves electricity? (a) iron one shirt at a time (b) use daylight to read (c) run fans in empty rooms (d) use old filament bulbs
2. 2.⏱️ A program says “wait 8750 ms”. How many seconds is that? =
3. 3.Which job needs a servo motor? (a) show a status light (b) move water to plants (c) turn to an exact angle (d) beep an alarm
4. 4.True or false: a wooden stick is a conductor. (a) True (b) False
5. 5.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the input (b) the process (c) the battery (d) the output
6. 6.🔋 Does a wind turbine give electricity or use electricity? (a) gives electricity (b) uses electricity
7. 7.💡 A red LED (it uses 2 V) is joined with a 100 Ω resistor to a 3.5 V supply. What current flows (in mA)?
8. 8.📏 How many ohms (Ω) is 8.7 kΩ?
9. 9.🔍 Which is the odd one out? (a) count button presses (b) decide if soil is dry (c) a temperature reading (d) compare with a limit
10. 10.🧮 Two resistors in parallel give a total that is … (a) more than either one (b) always zero (c) their sum (d) less than either one
11. 11.🔢 To run one loop of a plant-watering program, what comes right after “read the soil sensor”? (a) compare with the limit (b) wait a few seconds (c) switch the pump on/off
12. 12.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 59000 Ω resistor? (a) green-white-red (b) green-white-orange (c) white-green-orange (d) green-white-yellow
13. 13.💡 On an LED, is the leg by the flat edge the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
14. 14.🔐 Is it a good or a risky habit to read app permissions? (a) good habit (b) risky habit
15. 15.🔍 Which is the odd one out? (a) turn off unused gadgets (b) cover unused cameras (c) share camera links (d) set up with a parent
16. 16.⚠️ Is it safe to stay away from pylons? (a) not safe (b) safe
17. 17.🔍 Which is the odd one out? (a) a motor (b) a keypad (c) a motion sensor (d) a temperature sensor
18. 18.🔺 A current of 2.5 A flows through a 10 Ω resistor. What is the voltage across it (in volts)? =
19. 19.🤖 Does a hand pump usually have a microcontroller inside? (a) No (b) Yes
20. 20.🔘 A cell and a bulb are joined to two side-by-side paths: path 1 has switches A and B one after another, path 2 has switch C. A is OFF, B is ON and C is ON. Does the bulb glow? (a) No (b) Yes
21. 21.Which drawing is the symbol for a capacitor? (a) two equal parallel lines (b) a small empty box (c) a line lifted at a gap (d) triangle against a bar
22. 22.🔺 A 1.25 V supply is joined across a 5 Ω resistor. What current flows (in amperes)? =
23. 23.📏 Which unit measures how much a part resists? (a) ampere (A) (b) volt (V) (c) ohm (Ω) (d) watt (W)
24. 24.🔺 A current of 50 mA flows when 16.5 V is joined across a resistor. What is its resistance (in ohms)?
25. 25.Which of these mainly gives out light? (a) a doorbell (b) a siren (c) a night lamp (d) a table fan
26. 26.🔺 A current of 2.5 A flows through a 2 Ω resistor. What is the voltage across it (in volts)? =
27. 27.🤖 Microcontroller or laptop: which one runs one small program? (a) microcontroller (b) laptop
28. 28.🔢 To get a sensor reading onto a phone, which comes first: “the sensor measures” or “the cloud stores it”? (a) the cloud stores it (b) the sensor measures
29. 29.🔍 Which is the odd one out? (a) unplug idle chargers (b) use LED lamps (c) run fans in empty rooms (d) switch off empty rooms
30. 30.True or false: to share only needed data is a risky habit. (a) True (b) False
31. 31.⚡ A home appliance on the 230 V mains takes 4 A. What is its power (in watts)?
32. 32.🔺 A 3.75 V supply is joined across a 15 Ω resistor. What current flows (in amperes)? =
33. 33.True or false: “a button press” is the output. (a) True (b) False
34. 34.💡 A battery lights 2 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) the same (b) dimmer (c) brighter
35. 35.✏️ In a circuit diagram, wires are usually drawn as … (a) wavy lines (b) straight lines (c) dotted circles (d) little stars
36. 36.⚡ A 0.15 W device works on 1.5 V. What current does it take (in amperes)? =
37. 37.🔺 A current of 25 mA flows when 3.75 V is joined across a resistor. What is its resistance (in ohms)?
38. 38.True or false: to post your live location is a risky habit. (a) True (b) False
39. 39.🔺 In the V-I-R triangle, how do we find I? (a) I = V + R (b) I = V × R (c) I = V ÷ R (d) I = R ÷ V
40. 40.🗺️ In an input → process → output plan, is “a light level reading” the input, the process or the output? (a) input (b) process (c) output

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