Electronics Worksheet: Final Test

Electronics lesson 30: Final electronics test · Set 390 · 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.💡 A battery lights 3 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
2. 2.⚡ A home appliance on the 230 V mains takes 1.5 A. What is its power (in watts)?
3. 3.🧾 A family uses 190 units of electricity in a month and each unit costs ₹5. What is the bill (in ₹)?
4. 4.🔋 What should you do with used-up cells? (a) cut them open (b) give them for recycling (c) bury them in soil (d) throw them in a fire
5. 5.🌐 In an IoT system, which part shows data to you? (a) actuator (b) sensor (c) Wi-Fi (d) phone app
6. 6.⚡ What does a tube light mainly change electricity into? (a) light (b) movement (c) sound (d) heat
7. 7.🔺 A current of 25 mA flows when 3 V is joined across a resistor. What is its resistance (in ohms)?
8. 8.✏️ In a circuit diagram, which part is drawn as many long-short pairs? (a) LED (b) battery (c) cell (d) ammeter
9. 9.⚡ What does a rice cooker mainly change electricity into? (a) sound (b) heat (c) light (d) movement
10. 10.🔁 repeat 2 times { repeat 6 times { beep } }
    How many beeps are there?
11. 11.True or false: power is measured in amperes (A). (a) True (b) False
12. 12.True or false: two or more cell symbols is the symbol for a battery. (a) False (b) True
13. 13.🌈 In the resistor colour code, which number does green stand for?
14. 14.⏱️ A program says “wait 1000 ms”. How many seconds is that? =
15. 15.Which of these means the circuit is open? (a) the switch is ON (b) all wires are joined (c) the loop is complete (d) a wire is cut
16. 16.True or false: a circle with A inside is the symbol for an ammeter. (a) True (b) False
17. 17.True or false: to dry your hands first is not safe. (a) True (b) False
18. 18.🔺 A current of 2 A flows through a 15 Ω resistor. What is the voltage across it (in volts)? =
19. 19.🔍 Which is the odd one out? (a) take cells out after use (b) fly kites in open fields (c) stay away from pylons (d) use mains for a project
20. 20.💡 Why does an LED need a resistor in series? (a) to limit the current (b) to store charge (c) to change its colour (d) to make it brighter
21. 21.💡 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) the same (c) dimmer
22. 22.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark an 80000 Ω resistor? (a) white-grey-orange (b) grey-black-red (c) grey-black-yellow (d) grey-black-orange
23. 23.📏 Voltmeter or ammeter: which one measures current? (a) ammeter (b) voltmeter
24. 24.🔗 Series or parallel circuit: “each gets the full volts”? (a) series (b) parallel
25. 25.🔺 A 1 V supply is joined across a 2 Ω resistor. What current flows (in amperes)? =
26. 26.🔋 On a cell, does “usually the red wire” mean the + end or the − end? (a) + (positive) (b) − (negative)
27. 27.True or false: a microcontroller runs many apps at once. (a) True (b) False
28. 28.💡 A red LED (it uses 2 V) is joined with a 300 Ω resistor to a 3.5 V supply. What current flows (in mA)?
29. 29.🔁 x = 1
    repeat 4 times { x = x × 2 }
    What is x at the end?
30. 30.🔁 count = 3
    repeat 7 times { count = count + 4 }
    What is count at the end?
31. 31.True or false: to unplug idle chargers saves electricity. (a) False (b) True
32. 32.True or false: “own switch for each bulb” is true of a parallel circuit. (a) False (b) True
33. 33.⚡ What does a toaster mainly change electricity into? (a) light (b) sound (c) movement (d) heat
34. 34.💡 On an LED, is the round-side leg the anode (+) or the cathode (−)? (a) cathode (−) (b) anode (+)
35. 35.Which of these is true of a parallel circuit? (a) bulbs share the voltage (b) own switch for each bulb (c) a single current path (d) one bulb out, all go out
36. 36.🗺️ In an input → process → output plan, is “check if temp > 30” the input, the process or the output? (a) process (b) output (c) input
37. 37.🔁 repeat 4 times { repeat 4 times { beep } }
    How many beeps are there?
38. 38.Which of these is a good habit? (a) set a strong password (b) keep factory passwords (c) accept every permission (d) post your live location
39. 39.🧩 Which part changes electrical energy into movement? (a) an LED (b) a motor (c) a fuse (d) a resistor
40. 40.🌈 Which colour bands (1st digit, 2nd digit, multiplier) mark a 5900 Ω resistor? (a) green-white-red (b) green-white-brown (c) green-white-orange (d) white-green-red

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