What if a Needle hits the Earth at the Speed of light

Source: Ridddle

[urg]

This video is filled with misinformation and/or mistakes.

First, on nuke yield. There are only 3 nukes in recorded history with a yield arounding 10 kT of TNT or lower.

- Davy Crocket : 0.02 kt

- AIR-2 Genie : 1.5 kt

- Hiroshima's Little Boy : 13 to 18 kt


Every single nuke after Nagasaki's Fat Man (19 to 23 kt) has had yield over the 100kt, notably the Tsar Bomba, tested the 30th of October 1961 yielded around 50 Mt, which translate to 50 000 kt (yes fifty thousands).


Now, I assume you got to your 43 kt for your needle using the kinetic energy formula (KE = (1/2)*m*v²) assuming a needle weight of 4g, and with the speed of light at 299792458 m/s.


While this does give 43 kt of yield (more or less) you can't use this formula in this exemple, indeed this formula only works in Newtonian systems, which means it only works with "slow" speeds (lower than 1% of light speed).


Since we *are* talking about the speed of light here, you need to use relativistic kinetic energy, and the formula is quite a bit more complicated : E² = (pc)² + (m0c²)².


The difference with those formulas, is that the closer you are to the speed of light, the more energy you need to keep accelerating, and to get to the speed of light you need an infinite amount of energy, which means you get an infinite amount of kinetic energy as well.


Now for the sake of argument, and since I'm already this far in, let's see the Kinetic energy we get for a speed of 299 792 457m/s (1 m/s lower than speed of light), using the relativistic formula cited above we get this lovely result :


4 401 100 414 720 MJ, which translates to 1051 Mt of T.N.T, roughly 21 times the tsar bomba.


Now this would be devastating, but I don't think it would destroy earth itself. Alter the environment in a massive way, sure. Scorch the atmosphere and render it unlivable ? Probably. Tearing it to shreds ? I don't think so.

Thanks for coming to my Ted Talk

[luisnathanielmadraga]

Great now we’re gonna die if an astronaut has his/her villain arc

[klavesin]

Nothing with mass can move at the speed of light. Only close to the speed. And the energy depends on how close it is. Technically the needle can have any energy, 43 ktn, 43 mtn, gogol pentatons. Just accelerate it close enough to the speed of light.

[nishisuman]

When a needle hits the Earth at the speed of light, it would cause a tremendous amount of energy to be released. This energy could ignite the atmosphere, causing a chain reaction that would lead to widespread destruction.
The energy released from a needle hitting Earth at light speed would be similar to a large nuclear explosion. This explosion would possibly create a massive fireball, which would consume everything in its path.
The fireball would create a shockwave that would travel outward from the point of impact, causing even more destruction.
The shockwave would be strong enough to knock down buildings and cause widespread damage to infrastructure. The heat from the fireball would also cause widespread fires, which would be difficult to control due to the intensity of the flames.Potential shock waves created by the impact of the needle would be felt around the world. The energy released by the impact could cause the ground to shake, and the shock waves would travel through the Earth’s crust, causing earthquakes and other geological events.

The shock waves would also travel through the atmosphere, causing sonic booms that would be heard for miles around.
The impact of the needle would also cause a massive release of radiation, which would have a devastating impact on life on Earth. The radiation would be strong enough to kill most living organisms, and the fallout from the explosion would contaminate the environment for years to come.

[granddark]

That's impossible once the needle enter in atmosphere before the needle land it already melted

[sathishgarvandulags]

If a needle came at light speed to earth I think when it reach earth atmosphere it would be burnt. Did i only have this doubt..

[xogeneral]

wow thanks for the fact indiian guy, so where ddo you steal this from?

[Jusjax]

Bruh earth wouldn't torn apart it's like 3 tsar Bomba when needle hit the earth but it will cause some damage on earth

[relytunder]

terminal velocity & friction says this is just a cute thought

[OdysBrother]

Really guys... IF something flew at the speed of light. There would be no energy left in the universe. And it would probably be the next big bang.

Ok, long story short, if a photon flies with the speed of light, it is not a problem, because the mass is vanishingly small (really almost zero (you can call it zero, but I do not want to, because it still has a mass somewhere (we have been trying to determine the mass of a photon for decades, and to my knowledge we have not yet succeeded)). We assume that the photon still has a significant energy like 2eV.

Ok, let us just look at an atom. Atoms have a lot of mass compared to a photon. To be precise, an iron atom has 55.845 u (9.2732796 × 10^-26 kg just to give a reference with kg), it is still tiny but at least it has a measurable mass.

If just this one atom were to fly at the speed of light, it would need all the energy we have in the universe, and that would not even be enough to move at the speed of light.

Just as a calculation, the formula would be 1/2 * mass * velocity^2 = kinetic energy.
where ^2 is a superscript two (square)

1/2 * (0) * speed of light^2 = 2ev

1/2 * 55.845 u (9.2732796 × 10^-26 kg) * speed of light^2 = infinity

With fewer numbers and simpler presentation, though not scientifically correct, but easy to read for simple people.

(0) * speed of light = 2ev

56 u * speed of light = infinite

A single grain of sand has 10 trillion atoms. So:
10 trillion *56 u * speed of light = even more infinity.

Now a needle has several million trillion atoms. The same again, but with even more infinity.

So why a big bang? Quite simply. So much energy in such a small space that it would immediately implode. With the implosion, everything would collect in an infinitely small space, the density would increase infinitely with infinitely much energy. There is only one way out. In the other direction, away from all energy and matter, and very, very, very fast. An explosion. A big bang.

Now you know that if a pin could only move at the speed of light, everything would be over.

If you manage to get a pin to travel at exactly the speed of light, congratulations, you have created a new big bang and we are all dead.

Just hypothetically, if everything holds together and everything fits, the needle just goes through the Earth at the speed of light, and the Earth has no Infinite Energy to hold against, so nothing happens. No bang or anything.
Just zips through the Earth.

If you have read everything up to here, thank you very much for reading the long text. I would be happy if you would leave a thumbs up. That way I know that someone has read it and that it is not gathering dust somewhere in the infinity of the internet.
Thanks a lot 🙂

[shawnheim]

The answer to everything you just said is: no. If you don’t like that, there’s one other option: nope.

[Hi_im_negan]

To explain in a short fashion basically you my friend are entirely wrong the Earth itself will not evaporate from existence😑

[ravenandthestranger]

Little Boy was between 12 and 18 kilotons of TNT… Not 10 tons. Tsar Bomba was 50-58 megatons of TNT.

[WYTWDOWR]

Well to kill all arguments, the needle would burn up when it enters Earth's atmosphere.

[xiaoli]

The earth will not explode. The needle will cause a explosion near the size of a nuke

[thelazyphysicist]

You don’t have to go so far as traveling at the speed of light, all you need is to remove the drag and see what rain drops can do to you.😅

[itssaitamagaminglol]

So this is why goku is afraid of needles

[Willbertoslackbold]

I love people pretending that they know things and posting videos about it 😂

[Yutarikagetout]

I readed the entire thing and as a student with Harvard University and this guy that explained than this video is a lie is 100% correct about it won't destroy earth but it would do some damage

[excessro]

Silly indian, if a needle would travel at the speed of light the whole universe would “explode”.