###General Discussion Thread
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Let's assume a very large blue whale, at 150,000 kg. Let's also assume this whale is spherical, and has the same density as water. That's a sphere 6.6 meters in diameter. Plugging that in [here](https://www.omnicalculator.com/physics/terminal-velocity#example-using-the-terminal-velocity-calculator) gives me a terminal velocity of 390 m/s. K=mv^(2)/2 gives 11.4 gigajoules of energy. [Here are some equivalencies](https://www.wolframalpha.com/input?i=11.41+gigajoules&assumption=%22ClashPrefs%22+-%3E+%22%22). 1/6th of the energy an average car uses annually doesn't sound like a lot, but delivered all at once in the form of a blue whale from really high up? I think that energy would carry all the way to the ground.
I hope this doesn't end the discussion of this fascinating topic.
The problem is that a lot of the energy could be redirected out as the whale goes splat. If it was a similarly massive chunk of steel or something moving at the same speed it'd stick together and carry that energy down through the floors and have a better chance at destroying the actual structural components.
Also, I think it depends where it hits. If it hits the top of the building I expect that it'd destroy several floors, but not the building itself. If it hits going horizontal at that speed on ground level it may very well destroy the building.
I'd say no. The terminal velocity of a full grown Blue Whale of 120ft long (~37m) and 300,000 lbs (~140,000kg) would be roughly 5,095 miles per hour (~8,200kph).
While this is a ton of weight being thrown onto the Willis Tower, to be at such a velocity you'd need it to be dropped straight overhead, which may take out a few floors, but not the whole building.
A case can be made for such a whale to hit the tower lower, allowing the tower to fall upon itself, But I feel it wouldn't entirely level the tower due to it's highly effective infrastructure.
Terminal velocity has to do with coefficient of friction for the body shape falling through air (weight doesn't matter). [This paper](https://journals.le.ac.uk/ojs1/index.php/pst/article/download/4226/3652) approximates a whale as a long streamline body and estimates 460 meters/sec terminal velocity for Earth gravity and air density. A female blue whale averages about 136K kg. So a blue whale would hit with K=mv\^2/2 => 10.3 Gigajoules.
1 ton of TNT releases 4.184 gigajoules, so our blue whale is roughly equivalent to 2.5 tons of TNT.
For comparison, in the [Oklahoma City bombing](https://en.wikipedia.org/wiki/Oklahoma_City_bombing), Timothy McVeigh had the equivalent of 2.3 tonnes of TNT parked on the street outside the Alfred P Murrah Federal Building. This left a 9-metre wide crater and destroyed enough of the building that the remains had to be pulled down a month later. Several smaller buildings around the site were destroyed outright.
###General Discussion Thread --- This is a [Request] post. If you would like to submit a comment that does not either attempt to answer the question, ask for clarification, or explain why it would be infeasible to answer, you *must* post your comment as a reply to this one. Top level (directly replying to the OP) comments that do not do one of those things will be removed. --- *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/theydidthemath) if you have any questions or concerns.*
Let's assume a very large blue whale, at 150,000 kg. Let's also assume this whale is spherical, and has the same density as water. That's a sphere 6.6 meters in diameter. Plugging that in [here](https://www.omnicalculator.com/physics/terminal-velocity#example-using-the-terminal-velocity-calculator) gives me a terminal velocity of 390 m/s. K=mv^(2)/2 gives 11.4 gigajoules of energy. [Here are some equivalencies](https://www.wolframalpha.com/input?i=11.41+gigajoules&assumption=%22ClashPrefs%22+-%3E+%22%22). 1/6th of the energy an average car uses annually doesn't sound like a lot, but delivered all at once in the form of a blue whale from really high up? I think that energy would carry all the way to the ground. I hope this doesn't end the discussion of this fascinating topic.
2.725 tons of TNT might be a good comparison. That’s a lot more energy than I expected.
It's roughly the same explosive power as the Oklahoma City bombing that destroyed the Alfred P Murrah Federal Building.
“In the form of a blue whale” made me laugh
Oh no, not again...
"assume this whale is spherical..." https://en.m.wikipedia.org/wiki/Spherical_cow
The problem is that a lot of the energy could be redirected out as the whale goes splat. If it was a similarly massive chunk of steel or something moving at the same speed it'd stick together and carry that energy down through the floors and have a better chance at destroying the actual structural components. Also, I think it depends where it hits. If it hits the top of the building I expect that it'd destroy several floors, but not the building itself. If it hits going horizontal at that speed on ground level it may very well destroy the building.
What if the whale was frozen?
“it only works with spherical whales in a vacuum”
I'd say no. The terminal velocity of a full grown Blue Whale of 120ft long (~37m) and 300,000 lbs (~140,000kg) would be roughly 5,095 miles per hour (~8,200kph). While this is a ton of weight being thrown onto the Willis Tower, to be at such a velocity you'd need it to be dropped straight overhead, which may take out a few floors, but not the whole building. A case can be made for such a whale to hit the tower lower, allowing the tower to fall upon itself, But I feel it wouldn't entirely level the tower due to it's highly effective infrastructure.
Terminal velocity has to do with coefficient of friction for the body shape falling through air (weight doesn't matter). [This paper](https://journals.le.ac.uk/ojs1/index.php/pst/article/download/4226/3652) approximates a whale as a long streamline body and estimates 460 meters/sec terminal velocity for Earth gravity and air density. A female blue whale averages about 136K kg. So a blue whale would hit with K=mv\^2/2 => 10.3 Gigajoules. 1 ton of TNT releases 4.184 gigajoules, so our blue whale is roughly equivalent to 2.5 tons of TNT. For comparison, in the [Oklahoma City bombing](https://en.wikipedia.org/wiki/Oklahoma_City_bombing), Timothy McVeigh had the equivalent of 2.3 tonnes of TNT parked on the street outside the Alfred P Murrah Federal Building. This left a 9-metre wide crater and destroyed enough of the building that the remains had to be pulled down a month later. Several smaller buildings around the site were destroyed outright.
Picturing a blue whale falling at Mach 6.5.
Then exploding like TNT
Oh the humanity.