Watt’s Really Going On Inside the Lightbulb Part-2 [Rant Electronics #3]

Rishi SrivastavaRishi Srivastava
16 min read

✨Billy Wakes. Regret Glows.

“Where am I??”
Billy murmurs, waking up after being panned to sleep.

I’m sitting beside him, holding an old, burnt photo.
“O my dear Tungsten... how could you... how could y—”

“Watcha doing, bro?”

“AHHHHH! When did you wake up?! What did you hear?!”
I scramble, trying to hide her photos like I’m guilty of thermal infidelity.

“Hear ah? I saw everything bro. I’m gonna go tell her you still love her.”
Billy takes the initiative like he’s my emotional PR manager.

“Thank you so much bro! You want some ice cream? I’ll make you some!”
I grab the pan.

“Yea but... I don’t see how you’d make it on a pan—”

“Lemme show you. Come close.

“Clo—shit SHIT SHIS—no no sorry SORRYY—IT’S HOT, HOT!!”

“How the f hitting me make me feel heat?! Ain’t it supposed to be fire huh?!”

I look at him, red-faced, both from heat and shame.

“I am red… and this guy’s absurd questions don’t end.”

Billy sighs, delivers the final blow:

That’s why she left you, bro.

The pan left my hand…


🔥Thermal Vibes and the Cult of Heat Transfer

So? Heating a metal makes it… hot?
But what does “hot” even mean?

If you’ve been keeping up with Rant Electronics (bless your soul), you might recall that heat is just kinetic energy — or more specifically, vibrational energy.

And “being hot”? That’s basically your atoms shaking their atomic butts.
Yep, they’re vibing hard with the energy you dumped into them.

The more the heat, the faster they jiggle. And the faster they jiggle? The hotter things get.

🌡️ Zoom Out: Heat → Temperature

Now zoom out — like, way out.
On a macroscopic level, when you tally up all that jiggling across all the atoms in a body…

🎉 Congrats. You’ve got temperature.
(Just a statistical summary of atomic chaos.)

🧠 “SO how does this heat travel???”

Billy asks, rubbing the bump on his head from last night’s pan ambush.

“Ah yes, it’s basically the spread of brainrot,” I reply, deadpan.
“Like when one idiot starts dancing in the hostel corridor… and suddenly five more join in, unprovoked.”

“Ohhh just like that ah???”
Billy nods, thoroughly impressed with himself.

“No, dumbo,” I groan.
“There are three sacred paths.

🧙‍♂️ The Three Horsemen of Heat Transfer

Billy gasps.
“Wait—like some kind of boss battle? Do I get to choose one?”

Shut up and listen.
Welcome to: Conduction, Convection, and Radiation

✨Paths of Heat: The Sacred Paths

  1. 🧱 Conduction – The Pan-Slap Method

Heat transfer by touch. Simple. When two objects make contact — say, your bare hand on a steaming pan (cue Billy screaming) — the energy flows from the hot object’s atoms to the cold one’s.

On a microscopic level? It’s basically atomic MMA — high-energy atoms smashing into low-energy ones and forcing them to vibe too. This chaos spreads like dominoes through the material.

Conduction is elite when dealing with solids. Think of it as placing a calm person next to a dancing lunatic. One swing of the lunatic’s arm and boom — your calm friend’s personal space is invaded, rhythm unwillingly downloaded. (I meant hands. We don't want "freedom." This isn’t a political science class.)

  1. 🌪️ Convection – The Fluid Uprising

Ah yes, this one's about fluids — liquids, gases, and Billy’s emotional state.

Convection happens when heated particles move themselves around, carrying energy with them. It’s like the lower part of a fluid gets hot, becomes lighter, and rises up — and the colder, denser part sinks down to take its place. Cycle begins. Repeat.

Like bunk bed politics in the hostel — hot guy goes up, cold guy takes the lower berth.

Ever noticed how soup stirs itself when you boil it? That’s not magic. That’s convection currents — heat being yeeted around by the particles themselves. Self-service buffet of chaos.

  1. ☢️ Radiation — The Divine Detachment

Radiation is the celestial exhalation of thermal essence, unfurling across the cosmos in the form of electromagnetic undulations—birthed from the chaotic ballet of subatomic charges*, whose spasmodic accelerations rattle the very fabric of matter. Untethered by earthly mediums, this ethereal transfer unfolds via the* quantized communion of photons*, each a spectral envoy dancing to the decrees of* Planck’s cosmic liturgy*. Its fervor is dictated by the* edict of Stefan–Boltzmann*, while its chromatic metamorphosis—from sanguine red to searing white—is ordained by the sacred geometry of* Wien’s Displacement Canon*.*

Didn’t get any of that? Good.
Just think of it as invisible fire-light soaring through voids to make your skin tingle. (Or literal vibes travelling through space)
Worry not—we shall pry open this arcane vault in due time.


⚔️ The Betrayal of Metals

“So metals are the real chameleons, huh? Betrayers who shift colors under tension? Yes. Exactly like some of your first-year hostel ‘bros’. Trust me. Everything changes. Every group bre—”
Bro bro calm down!
Billy’s back. And this time, he’s here to observe… and judge.

“Uh, yea. Bring your hand close to this heated pan. Don’t touch—just hover. What do you feel?
Warmth, right?
But how? Air conduction? NOPE. Air is the worst conductor of heat—its atoms are spaced out like a resentful bloodline at Christmas.

So what’s happening?

Magical heat waves—radiation.
Heat a metal—heck, heat anything—and it starts firing off invisible energy bullets. The first to launch? Infrared (IR) photons.

Billy’s Brain‑Melt, Part I

“If IR’s real, why can’t I see it?”
“And why doesn’t my friend burst into flames when I blast him with the TV remote?”

Patience, Billy. First, let’s spin the temperature dial.

Turning Up the Heat

As things get hotter, they vomit photons that are stronger, faster, and shorter‑waved.
Think of each photon as a courier pigeon from Hell, carrying two bits of intel:

CodeWhat It Means
FrequencyHow fast the wings flap
WavelengthHow wide those flaps spread

When that photon smack‑talks an atom, the message turns into atomic twerking. Wavelength is basically how long an atom shakes, and frequency is how many times that shake happens in one second. They’re inversely related: if one goes up, the other drops.

Makes sense — you can’t do long slow shakes ten times in one second. Have mercy on the atoms.

💡
Billy’s Fact Corner: A photon is the smallest packet of light — like a mini energy grenade. Its energy depends on its frequency, which is related to how it wiggles. The higher the frequency, the more punch it packs. Energy of a photon = Planck’s Constant × Frequency = (Planck’s Constant × Speed of Light) ÷ Wavelength. So yeah — red, blue, IR — they’re all photons, just wearing different costumes. ““Bigger wavelength → lower frequency → weaker photon.””

So low‑frequency IR lands on your skin like a polite cheek‑kiss, transferring a gentle jiggle.
Crank the heat and you spawn ruder photons that slap instead of kiss—atoms vibrate harder, you yelp louder.

Raising the temperature even more!, Now you start seeing things, not because you are delusional, but because now the photons with even more higher energy show colour—not just invisible IR anymore. First, a dull red. Then bright red. Orange. Yellow. White.

It’s like your toaster leveling up from shy blush to full anime power mode.

There’s a whole cabal of equations behind this — Planck’s Law for the energy soup, Stefan-Boltzmann for how intense it is, and Wien’s Displacement Law for the exact color it glows.

But don’t worry — I won’t throw a textbook at you... yet.

“DON’T SLEEP YET, STAY WITH ME — STAY WITH ME!!”

🚨 Superfast Recap Time!
Heat up a metal → It starts whispering soft, low-powered IR radiation → You feel warm but see nothing.
Crank the heat higher → The radiation gets louder and angrier → Boom! You start seeing colors — red, orange, white.
And with that, we’ve technically answered our original question: “How do lightbulbs glow?”

But oh no — we're not done.
We’ve just opened the door to a thousand other rants!


🧲 IR: The Heat You Can’t See (But Can Feel)

It’s the ghost of photons that haunts your skin.

Now focus up! splashes water on your face

Ever wonder why you never noticed your TV remote had an IR blaster — until you saw it glowing on a camera? Or why standing near a campfire feels warm even before you touch anything?

It’s all about two things:

  1. How powerful the IR photons are

  2. How many of them are coming at you

Let’s introduce the electromagnetic radiation spectrum — it links a source’s temperature (and energy) to the type of photons it emits.
But unlike school grading systems, this one isn’t made of neat boxes. It’s a continuous spectrum — no sharp lines, just gradual shifts.
At one range, you get IR (Infrared). A bit higher? Visible light. Higher still? UV, X-rays, gamma rays. A full photon buffet.

But here’s the catch — even inside the IR range, there’s a lower and upper class.

📉 Low-end IR photons = gentle, broke boys — not enough energy to do anything serious.
📈 High-end IR photons = rich and ruthless — they will toast your skin like marshmallows at a cult bonfire.

So yeah, your TV remote’s IR is a broke boy. You can’t cook your annoying friend with it, no matter how many times you mash the volume button.


👁️ Seeing Heat, Feeling Light: What Even Are You?

IR hurts. Red doesn’t. Glass sees. Metal screams.
Your body picks sides.

Hold up—aren’t all colors technically radiation?
And aren’t visible photons more energetic than IR ones?
Then why doesn’t blue light roast my face while yellow bulb light feels like it’s sunbathing my soul?

Ah, now you’re catching the pattern.

See, visible light doesn’t heat you up like IR does because your atoms are... not racist, no-no — let’s call them frequencist.
They vibe only with photons of just the right frequency, and they ghost the rest like your crush reading your “hey :)” for 7 business days straight.

So when IR photons hit your skin — boom, full-on atomic rave party. They match the frequency your atoms love, so heat gets transferred.
But visible light photons? Even though they carry more energy, they’re just like, “Hey,” and your atoms go, “nah, not my type.”


🕶️ “But why is IR invisible?! I wanna see the cold side of the pillow!!”

It’s not you, it’s biology.
Our bodies are built with thermoreceptors that feel energy transfer (like IR), but our eyes are tuned only to a specific photon band — the visible spectrum (~400–700 nm).
IR radiation has longer wavelengths (~700 nm–1 mm), which don’t trigger the opsins in your eye’s photoreceptors.

So no — you don’t see IR. You feel it.

But don’t lose hope — not everyone’s this blind.
Some animals, like snakes and beetles, can see IR. And machines? Cameras can see a slice of it too.
So yes — you, your lonely resistor, and your crusty old TV remote are glowing... just not in your world.

Your phone’s camera, on the other hand? It sees the remote’s IR blaster as a bright flash. But it can’t see the warm aura of your hand soldering project — that’s too low-energy for it to care.

🧪 Wait… Why Is Glass Transparent?

Here’s one of those "duh" facts that turns into a full-blown existential crisis if you think too hard about it.

So tell me, Mr. It’s-So-Obvious, why is glass transparent?

No, seriously. WHY?

Truth is stranger than the strangest fiction — but we rarely bother looking closely.

Here’s the real deal:

We see objects when light bounces off them. That’s it.
You shine white light (a chaotic soup of all visible wavelengths) onto something.
Now what happens?

If the object’s atoms "vibe" with certain photon frequencies, they absorb that energy — boom, color gone.
The rest? They either get reflected or just pass through, depending on the structure or arrangement of atoms of the material—

you wanna go there? HUH!? You wanna dip your toes into chemistry??
Huhuhuhu.
You dare challenge the periodic demons?
You dare enter the orbital abyss??

Come to the next section if you dare. 🔥💀

And the ones that bounce back?
Those are the photons that smack your retina — that’s the color you perceive.
(Important: We’re talking visible light only. Even if something reflects IR, you won’t see it — you’d just feel it. Like betrayal.)

Now take glass. It’s not magical. It’s just... indifferent.

The atoms in glass don’t vibe with any of the visible spectrum frequencies.
They’re like: “Nah, not my frequency. You may pass.”
So instead of absorbing or reflecting, the photons just walk right through, unbothered.

That’s why you see through it. It’s not not there, it’s just a very chill landlord.

But — plot twist — if you switch the vibe?

Say, UV light? Now glass turns into a strict bouncer.

UV photons do match the atomic frequency of glass.
So they get absorbed, not transmitted. That means:
If humans could see UV? Glass wouldn’t be transparent. It’d look black. Or a murky, evil purple at best.

☀️ The SUN is a Deadly Laser?

Why does sunlight feel hot?
Why does red-hot metal hurt before you even touch it?
Why does a campfire singe your soul just by existing?

Well, here’s the thing — I never said hot objects stop giving off IR when they get hotter. No, no, no. That’s not how this chaotic photon rave works.

In fact, they give off even more IR, alongside a whole buffet of higher-energy photons.
The Sun? That diva emits radiation across all frequencies — it’s got no frequency-phobia. IR, visible light, UV… it’s throwing an intergalactic rave and everyone’s invited (except your melanin, it’s overworked).

So yes, that’s why the Sun burns and blinds. It’s not just light — it’s a full-on photon stampede.

As for red-hot metals and campfires:
They’re like awkward teenagers — not fully glowing up to white light levels yet, but definitely IR-rich and vibing hard. Their heat zones aren’t even — some parts spit out more IR, others less, and your skin just… receives whatever insult it’s handed.

In short:
Hot things never stop doing IR. They just add more spicy photons to the mix.


⚗️ Material Chemistry: Whether You Like It or Not

So every atom owns some energy levels, right?
Then along came a fancy German gent, who cranked physics to the MAX by slapping a “Planck” of quantisation on reality.

Quantisation = “there’s a smallest unit, deal with it.”

You can have 1 light‑bulb, 2 light‑bulbs… n light‑bulbs.
But 0.7 of a bulb? ⅓ of a bulb? Nope. Discreteness, baby.

That was obvious for light‑bulbs, but Planck dropped the bomb that energy itself is quantised.
Atoms can’t wiggle at “0.23 frequency.”
They have fixed energy states—like dancers who only hit specific beats.

Level‑Up Metaphor

Picture an atom’s energy states as platform‑game levels.
The gaps between levels are band gaps.

  • A photon arrives.

  • If its energy exactly matches the gap, the electron jumps to the next platform.

  • Too low? Too high? The electron shrugs. Photon gets ignored (passes through) or bounced (reflected).

No “just a little extra.” Exact cover charge or GTFO.

Three Main Scenarios

Material TypeElectron StatusPhoton FateWhat You See
MetalsElectrons are free & rowdyPhoton energy gets re‑emitted almost instantlyMirror‑like reflection (shiny)
Insulators / GlassElectrons bound & pickyVisible photons don’t match any jump → pass throughTransparency
Pigmented stuff / Paint / SkinSome photons match, others don’tMatched ones absorbed, rest scatteredColor (only reflected wavelengths hit your eyes)

UV & IR get separate VIP rules depending on the material’s band gap.

TL;DR

  • Free electrons? Mirror city.

  • Wrong‑energy photons? Ghost mode → transparency.

  • Just‑right photons? Absorbed → color or heat.

And yes, that’s why glass ghosts visible light but body‑slams UV, while metals reflect everything like narcissists at a fun‑house.

⚠️ And about that “continuous spectrum”?
Yeah, it’s a lie.
What looks smooth and seamless is actually tiny quantised jumps too fast and close together for your eyes (or basic instruments) to resolve. It’s not truly continuous—it’s just high-res discrete stuff masquerading as a smooth flow. Like watching 60 FPS video and forgetting it's just a slideshow of still frames.
So yes, even sunlight—the gold standard for a “continuous spectrum”—is still just a blur of discrete quantum transitions happening across countless atoms and molecules.


The Biology of Heat and Light Perception

I ain’t writing shit here.
This is a whole different rabbit hole—biology, neurons, rods, cones, thermal receptors, and whatnot.
I’m opening the floor for a bio nerd to collab. If you’re one of those people who thinks in terms of action potentials and ion channels, hit me up.
I’ll link your article right here, front row.

Because frankly, my understanding of bio is limited to:

  • mitochondria = powerhouses

  • ATP = expensive energy coins

  • and pain = when your neurons gossip too loudly


🧠 Facts: Cuz maybe you need something light

Some weird historical and science stuff that feels like side quests you didn’t sign up for—but are now stuck in.

1. Glass is a Slow Liquid?
Nope. That old "church windows are thicker at the bottom because glass flows" myth? Totally debunked. Glass is an amorphous solid. It doesn’t flow; it’s just been through centuries of bad architecture and worse science teachers.

2. Ancient Romans used asbestos napkins
They’d toss them into the fire to clean them. No joke. They loved how asbestos was “indestructible.” They also died from it. Just some classic ancient luxury with a side of lung disease.

3. The guy who discovered oxygen got ignored
Joseph Priestley discovered oxygen, but he didn’t realize what he had. Antoine Lavoisier swooped in later, named it, understood it, and got the credit. Welcome to the Scientific Hunger Games.

4. Human eyes can detect individual photons
In complete darkness, your eye can pick up a single photon. You won’t consciously register it, but your rods and cones are literally built different.

5. Tungsten has the highest melting point of all elements
Over 3400°C, and it's still chillin'. That’s why your lightbulb filaments are tungsten—they can take the heat... unlike your laptop during Zoom calls.

6. Early mirrors were pools of dark water or obsidian slabs
People literally stared into puddles or polished black stones to see themselves. Narcissism has always found a way.

7. Quantum Tunneling sounds fake, but it’s real
Particles can break through energy barriers without enough energy—like a ghost walking through a wall… except it's math-approved.

8. Edison didn’t invent the lightbulb
He made it marketable. The actual idea had been around. But he was the Steve Jobs of 1879—not the first, just the flashiest.


Philosophy

🧠 "A glowing bulb is just ordered chaos."

– For the existential nerds.
Electrons race madly, atoms vibrate like drunk dancers — and yet we call it light. Maybe brilliance is just focused madness.”


Next on Rant Electronics

We’ve roasted the filament — now it’s time to side-eye those smug white LEDs. Ever wondered why they glow like saints but don’t sweat like sinners?

How do they manage to light up a room without even breaking a sweat — are they even real?

Before we spill the secrets of these glowsticks from the future, let’s take a detour to meet their older, quieter cousin: the diode.

Spoiler: this one doesn’t even try to shine — but it’s the unsung hero behind every LED flex.

Till then, rest. Restore your attention span. And let me get back to writing poems for my diodes.


Welcome to Rant-Electronics.
This is not a tutorial.
This is therapy.

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Written by

Rishi Srivastava
Rishi Srivastava

BTech ECE student | Passionate about electronics, AI, and GPUs. Writing to make tech simple. Founder of SiliconPen.com.