Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 53 · 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.🔗 Series or parallel circuit: “used in house wiring”? (a) parallel (b) series
2. 2.True or false: on a cell, “the end with a bump” means the − (negative) end. (a) True (b) False
3. 3.✏️ Why do engineers draw circuits with symbols? (a) to make it colourful (b) symbols are heavier (c) quick and clear for all (d) to hide the circuit
4. 4.🔁 total = 0
   for i = 1 to 5 { total = total + i }
   What is total at the end?
5. 5.True or false: if the loop is complete, the circuit is closed and current flows. (a) False (b) True
6. 6.🤖 if (sound > 70) { red LED ON } else { green LED ON }
   The sound sensor reads 86. What happens? (a) red LED ON (b) green LED ON
7. 7.🌐 A weather station sends one reading every 20 seconds. How many readings does it send in 7 minutes?
8. 8.True or false: to read app permissions is a risky habit. (a) False (b) True
9. 9.🔁 A bulb has two contacts. How many must be joined into the loop for it to glow? (a) it does not matter (b) both of them (c) none (d) only one
10. 10.✏️ In a circuit diagram, which part is drawn as a small empty box? (a) cell (b) switch (c) resistor (d) ammeter
11. 11.🔍 Which is the odd one out? (a) a torch (b) a night lamp (c) a street light (d) a table fan
12. 12.🔐 Privacy for a smart device means controlling … (a) its colour (b) its battery size (c) how loud it beeps (d) who can see your data
13. 13.True or false: on an LED, the round-side leg is the cathode (−). (a) False (b) True
14. 14.🔐 A smart-camera app asks for your school name and home address. What should you do? (a) type it all in (b) ask a parent first (c) share it with friends (d) post it online
15. 15.Which of these mainly makes sound? (a) a school bell (b) a street light (c) a tube light (d) a water heater
16. 16.⚡ A 0.6 W device works on 3 V. What current does it take (in amperes)? =
17. 17.🔋 5 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)? =
18. 18.⚡ A 0.3 W device works on 1.5 V. What current does it take (in amperes)? =
19. 19.⚙️ Which actuator would you use to move water to plants? (a) a servo motor (b) a pump (c) an LED (d) a buzzer
20. 20.🧮 A 47 Ω resistor is joined in series with two equal 220 Ω resistors that are in parallel with each other. What is the total resistance (in ohms)?
21. 21.Which of these is the input? (a) a motion sensor signal (b) the fan starts (c) count button presses (d) the pump turns on
22. 22.True or false: “one bulb out, all go out” is true of a parallel circuit. (a) True (b) False
23. 23.True or false: a safety pin is an insulator. (a) False (b) True
24. 24.🔁 repeat 2 times { repeat 2 times { beep } }
    How many beeps are there?
25. 25.💡 A battery lights 3 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) dimmer (b) the same (c) brighter
26. 26.💡 An LED (with its resistor) is on pin 8. All pins start LOW. The program runs once:
    set pin 7 HIGH
    set pin 8 HIGH
    set pin 7 LOW
    set pin 7 LOW
    set pin 8 HIGH
    Is the LED ON or OFF at the end? (a) OFF (b) ON
27. 27.Which of these mainly gives out light? (a) an LED lamp (b) an electric toy car (c) a mixer grinder (d) an electric drill
28. 28.🔋 5 identical 1.2 V cells are joined side by side in parallel (all + ends together, all − ends together). What is the voltage across them (in volts)? =
29. 29.True or false: a toggle switch slides side to side. (a) False (b) True
30. 30.🧾 A family uses 140 units of electricity in a month and each unit costs ₹7. What is the bill (in ₹)?
31. 31.Which drawing is the symbol for an LED? (a) a line lifted at a gap (b) two equal parallel lines (c) triangle, bar and arrows (d) a circle with A inside
32. 32.⏱️ How many milliseconds are in 1 second? (a) 60 (b) 10 (c) 1000 (d) 100
33. 33.🔺 A current of 3 A flows through a 3 Ω resistor. What is the voltage across it (in volts)? =
34. 34.What does the Wi-Fi link do? (a) measures the real world (b) carries the data (c) shows data to you (d) stores data online
35. 35.True or false: “an LED lights up” is the output. (a) True (b) False
36. 36.🔺 A 9 V supply is joined across a 3 Ω resistor. What current flows (in amperes)? =
37. 37.True or false: on a cell, “usually the red wire” means the + (positive) end. (a) False (b) True
38. 38.True or false: a microcontroller runs one small program. (a) True (b) False
39. 39.💡 An LED is joined to a 5 V battery through a 1000 Ω resistor; its long leg goes to the + side and its short leg to the − side. What happens? (a) lights up (b) may burn out (c) does not light
40. 40.💡 A battery lights 5 identical bulbs joined in parallel. One more identical bulb is added in parallel. How do the bulbs glow now? (a) brighter (b) dimmer (c) the same

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