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tomswartz07 | 6 years ago

Water is heavy.

If you drop water on a structure like this, you end up having a collapsed building that is also on fire.

discuss

order

jimmaswell|6 years ago

Then why doesn't it collapse when it rains?

Edit: Note the absolute phrasing of the parent comment and that the spray force in a strong downpour isn't much less than what's done with firefighting planes in situations that call for that level of pressure.

stcredzero|6 years ago

The rain falls over an extended period of time, not all at once as one glob. Only several drops are hitting you at any given instant in the rain, so you are only subjected to minuscule amounts of force at any given instant.

The difference would be like standing in the shower for 40 minutes, versus being hit my an entire tub full of water going at the same speed all at once.

I remember during the Khan Academy controversy a few years back, an educator commented on reddit about the difficulty in teaching some kids about rates. Some kids just don't get rates. They think of speed as something like "a feeling of intensity." They just don't have an abstract, generalized understanding of "N things per unit time."

Think about that for a moment. Think about all of the potential for miscommunication.

jon-wood|6 years ago

Generally when it rains you don’t go from nothing to several tons of water all hitting at once.

purerandomness|6 years ago

Because most times when it rains, it's also not on fire.

r00fus|6 years ago

Rain also doesn't put out major fires by itself.

mikejb|6 years ago

Because it doesn't rain tons of water in less than a second.

noja|6 years ago

The rate is different.

Lots of water at once versus less spread over a long time.

pfortuny|6 years ago

Because. It. Is. Rain.