Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 828 · 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.💡 On an LED, is the longer leg the anode (+) or the cathode (−)? (a) anode (+) (b) cathode (−)
2. 2.🔍 Which is the odd one out? (a) an app-controlled bulb (b) a fitness band with app (c) a smart energy meter (d) a pencil sharpener
3. 3.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 210 Ω resistor? (a) red-brown-brown (b) red-brown-black (c) red-brown-red (d) brown-red-brown
4. 4.🔍 Which is the odd one out? (a) a steel coin (b) a dry cork (c) a metal paper clip (d) a brass key
5. 5.🔺 In the V-I-R triangle, how do we find I? (a) I = V + R (b) I = V ÷ R (c) I = R ÷ V (d) I = V × R
6. 6.🔐 Who should decide which smart devices go in a child’s room? (a) a parent or guardian (b) an online stranger (c) the app’s adverts (d) nobody at all
7. 7.🧮 Resistors of 100 Ω, 150 Ω, 330 Ω and 100 Ω are joined in series. What is the total resistance (in ohms)?
8. 8.🔁 total = 0
   for i = 1 to 3 { total = total + i }
   What is total at the end?
9. 9.🔌 Is a temperature sensor an input or an output for a microcontroller? (a) input (b) output
10. 10.Which of these is not safe? (a) dry your hands first (b) keep drinks far away (c) stay away from pylons (d) open a phone charger
11. 11.True or false: an electric drill mainly makes sound. (a) False (b) True
12. 12.🔋 How many volts does one ordinary torch cell give? (a) 1.5 V (b) 15 V (c) 230 V (d) 0.5 V
13. 13.True or false: to leave fridge door open saves electricity. (a) False (b) True
14. 14.Which of these is an input? (a) a water pump (b) a push button (c) a servo motor (d) a motor
15. 15.⏱️ loop forever { LED ON; wait 150 ms; LED OFF; wait 50 ms }
    How many times does the LED blink in 10 seconds?
16. 16.⚡ What does an exhaust fan mainly change electricity into? (a) light (b) movement (c) sound (d) heat
17. 17.Which of these is not safe? (a) dry your hands first (b) keep drinks far away (c) build with an adult near (d) use a cable with cuts
18. 18.🤖 Microcontroller or laptop: which one has no screen of its own? (a) laptop (b) microcontroller
19. 19.🔘 Which kind of switch springs back when let go? (a) a push button (b) a reed switch (c) a slide switch (d) a toggle switch
20. 20.🤖 In “if (temp > 30)”, what runs when temp is exactly 30? (a) both parts (b) the if part (c) neither part (d) the else part
21. 21.🌐 Is a pencil sharpener an IoT device? (a) an IoT device (b) not an IoT device
22. 22.True or false: to warn of a gas leak, use a gas sensor. (a) True (b) False
23. 23.True or false: “one out, the rest glow” is true of a series circuit. (a) True (b) False
24. 24.🔍 Which is the odd one out? (a) a ceiling fan (b) an electric toy car (c) a table fan (d) a night lamp
25. 25.🧮 Four equal 200 Ω resistors are joined in parallel. What is the total resistance (in ohms)?
26. 26.True or false: the push of a cell is measured in volts (V). (a) True (b) False
27. 27.🔢 To run one loop of a plant-watering program, what comes right after “compare with the limit”? (a) read the soil sensor (b) wait a few seconds (c) switch the pump on/off
28. 28.What does a tilt switch do? (a) springs back when let go (b) slides side to side (c) flips up or down (d) closes when tipped over
29. 29.🔺 A current of 2 A flows when 8 V is joined across a resistor. What is its resistance (in ohms)?
30. 30.True or false: a microcontroller uses very little power. (a) True (b) False
31. 31.🌈 A resistor has the colour bands grey, green, red. What is its value in kilo-ohms (kΩ)? =
32. 32.🔁 count = 1
    while (count < 11) { count = count + 5 }
    How many times does the loop run?
33. 33.⚠️ About how many volts do home sockets in India supply? (a) 1.5 V (b) 230 V (c) 9 V (d) 12 V
34. 34.True or false: on a cell, “the end with a bump” means the + (positive) end. (a) True (b) False
35. 35.💡 4 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. Bulb 1 is taken out of its holder. Does bulb 3 glow? (a) No (b) Yes
36. 36.Which of these is an IoT device? (a) a pencil sharpener (b) a plain wall switch (c) a Wi-Fi doorbell camera (d) a paper calendar
37. 37.🗺️ In “input → process → output”, which part is the decision the program makes? (a) the input (b) the battery (c) the process (d) the output
38. 38.Which of these is a good habit? (a) accept every permission (b) share camera links (c) install software updates (d) tap unknown app links
39. 39.What does the actuator do? (a) measures the real world (b) stores data online (c) reads values, decides (d) acts on a command
40. 40.🔍 Which is the odd one out? (a) share camera links (b) keep factory passwords (c) log out of shared phones (d) post your live location

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