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Comment by munk-a | Hacker News Reader

I'd be amazed if the density of weight on the ship is such that an arbitrarily large fleet of Chinooks could actually safely accomplish this. And helicopters flying in a dense formation under strain is quite likely to result in a lot of really big problems.

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Yeah because what we really need to fix this situation is several hundred giant blenders exploding in mid air fireball of high velocity steel on top of the jammed ship

Absolutely glorious, though I'm wondering what recent synced drones could do for that instead of faking foreworks.

The rotor wash beneath it all would be breathtaking.. and might blow all the water out of the canal. :)

Somebody get Randall Munroe on the phone - I think we've found the next What-If topic.

Which makes me think - what about using all these choppers to blow the water in - and keep it there? :).

(I assume this is an equivalent problem to the lifting problem, as the extra pressure they'd be fighting would be that of the ship displacing water.)

That's actually an interesting idea - set up a temporary lock/dam on either side of the ship to float it. If, instead of a boring dam made out of concrete or something "normal" we used a fleet of Chinooks then all the better!

I do believe this is probably one of the solutions that's being investigated but I also believe it's

1. Super expensive to construct an impromptu dam under water

2. Floating a listing ship can result in more severe listing if you're not careful (See, for instance, the fact that when a ship beaches itself while the tide is out it's initially bad news - and when the tide starts to come back in it becomes significantly worse news.

Learning and humor are fun together!

Now I wonder...

Let's assume it was possible. Would the force of lifting that much mass be enough to shift the earth in a measurable way? (I'm assuming it would be a lot stronger lifting it into the air than what floating on the water produces, but have no idea what the math would be)

F=ma no matter what, so if things aren't accelerating, the force isn't changing, it's just being transferred to the earth by other means. In this case, it would be through the air rather than the water.

It is as it's lifted though, right?

I don't understand the question. Try restating the question without using the word "it".

The ship is accelerating as it's lifted though, right?

Yes, but the ship is already being accelerated upwards by the surface of the earth at 9.8 m/s^2. If you were to lift it, you'd do it very, very slowly, so you'd increase the acceleration (temporarily) to, say, 9.8000001 m/s^2. The extra force required to do that is very small.

Note that ships actually are accelerated up and down in the Panama canal, which has locks. (The Suez doesn't.) That amounts to pretty much the same thing. It doesn't matter whether the forces are transferred to the earth via a column of water or a column of air.

Because this is physics I wanted to clarify that the ship is not being accelerated upwards by the surface of the earth at 9.8 m/s^2 it is being effected by a static force that is countering an opposing force that would cause it to accelerate downwards at 9.8 m/s^2 that causes it to remain in a state of rest. To lift the ship off the ground you not only need to out pace the difference between the static force in agreement and the opposing force - but the static force will not contribute to motion so you do correctly need a force that would result in an acceleration of 9.800001 m/s^2 in the absence of gravity.

Since the static force in opposition won't contribute towards upward motion you actually need to supply the full amount of force to lift it - not just enough to barely nudge the need by .00001 m/s^2

In terms of whether that force would cause any effect the answer is yes (because everything is an effect) and effectively no since as ridiculously heavy as this container ship is it is absolute peanuts compared to the mass of the earth nuclear explosions that produce megatons of force are still immensely negligible, ditto for super massive volcanoes. A volcanic explosion large enough to derail the earth's rotation by a day would definitely be an extinction level event for all of the complex life forms on earth. But, that said, every little thing does contribute in its little way.

Lastly - yea, the presence of locks in the panama canal does mean that ships are regularly accelerated upwards and downwards without any noticeable effect - if that change in elevation was executed by explosives or chinooks there would be slight variations in the force but they'd be mostly inconsequential on the scale of things.

> the ship is not being accelerated upwards by the surface of the earth at 9.8 m/s^2

Actually it is:

https://www.thegreatcoursesdaily.com/einsteins-experimental-...

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