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How to use gdb in Ubuntu Terminal

Here's a practical, minimal guide for using GDB in Ubuntu terminal — from launching to setting breakpoints and navigating your code. 🧰 Step 1: Compile with Debug Symbols Use -g and disable optimizations ( -O0 preferred for debugging): bash Copy Edit g++ -g -O0 -o myprog myprog.cpp 🚀 Step 2: Launch GDB bash Copy Edit gdb ./myprog You'll see a (gdb) prompt. 🎯 Step 3: Set Breakpoints You can set breakpoints in three main ways : ✅ a. At a function gdb Copy Edit (gdb) break main ✅ b. At a specific file and line gdb Copy Edit (gdb) break myprog.cpp:42 ✅ c. At a method in a class gdb Copy Edit (gdb) break MyClass::doSomething If the symbol is mangled (C++), GDB usually demangles automatically, especially if compiled with -g . ▶️ Step 4: Run the Program gdb Copy Edit (gdb) run 🧭 Step 5: Navigate Command Meaning next or n Step over current line step or s Step into function call finish Run until current function returns continue or c Continue until...
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Inert gas in Earth's atmosphere: Discussion with chatGpt

Query:
Neon gas is a inert gas. And in tubelight mostly they fill in this gas. But is this gas so much available in earth atmosphere so that it can fill so many tubelights?
ChatGPT said:

Great question! You're absolutely right—neon is a noble (inert) gas, and it's indeed used in certain types of gas-discharge lighting, especially "neon lights" (the bright red-orange ones you often see in signs). However, neon is not the gas typically used in regular household or office tube lights, like fluorescent lamps.

Let's clear up a few points:

1. Which gas is used in tubelights (fluorescent lamps)?

In standard tubelights (fluorescent lamps), the tube is usually filled with:

  • Argon gas (or sometimes a mix of argon and a bit of krypton),

  • Plus a small amount of mercury vapor.

When electricity excites the mercury vapor, it emits ultraviolet (UV) light, which hits the phosphor coating inside the tube, causing it to glow in visible light.

So: Neon is not typically used in fluorescent tubelights.

2. Is neon abundant in Earth’s atmosphere?

  • No, it's quite rare.

  • Neon makes up about 0.0018% (by volume) of the Earth's atmosphere.

  • That’s 18 parts per million, which is much less than argon (~0.93%).

3. How do we get neon for neon signs?

Neon is extracted through the fractional distillation of liquid air, just like oxygen, nitrogen, argon, and other atmospheric gases. Even though it’s rare, air is free and plentiful, so industrial plants that produce oxygen and nitrogen as primary products can also extract neon efficiently, though in smaller quantities.

Summary:

  • Tubelights use argon and mercury, not neon.

  • Neon is rare in the atmosphere, but can still be harvested in useful amounts via air separation.

Would you like a diagram comparing gases in the atmosphere and their uses in lighting?

You said:
Ok, so argon n krypton are also inert gas (Elements). Are they enough available?
ChatGPT said:

Yes, argon and krypton are also inert (noble) gases, and while both are rare compared to nitrogen or oxygen, they are available in enough quantities for industrial and commercial use, including in lighting like tubelights.

Here’s a breakdown:

🧪 Argon (Ar):

  • Abundance in air: About 0.93% by volume.

  • That’s 9,300 parts per million (ppm) — very abundant among noble gases.

  • It’s the third most common gas in Earth's atmosphere after nitrogen and oxygen.

  • Common uses:

    • Filling gas in fluorescent lights, incandescent bulbs, and some lasers.

    • Used in welding as a shielding gas.

    • Used in high-purity environments (e.g., electronics manufacturing).

✅ Conclusion: Argon is easily available and inexpensive to extract.

🧪 Krypton (Kr):

  • Abundance in air: About 1 part per million (ppm).

  • Much rarer than argon, but still extractable via fractional distillation of air.

  • Common uses:

    • In high-performance lighting (e.g., some halogen lamps).

    • In insulated windows (as a thermal insulator).

    • In scientific and medical equipment.

✅ Conclusion: Krypton is rarer, but used in small quantities, so supply is generally sufficient for its niche applications.

🌍 Summary Table:

Noble Gas% in AtmosphereAvailabilityCommon Uses
Argon0.93%HighLights, welding, insulation
Krypton~0.0001% (1 ppm)ModerateSpecial lighting, insulation
Neon~0.0018%LowNeon signs

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