April 1st, 2009

Ceci n'est pas une personne.

(no subject)

Some useless information based on wild assumptions...

The Space Needle elevator goes up and down at 10mph, except in high winds, when they drop the speed to 5mph.

Someone on my Flickr account told me the elevator was paced such that when you go down the rain appears to just hover outside the windows of the elevator.

Now, I had been taught the terminal velocity of rain was 20mph, so to find out who was right, I did some research.

It turns out the rate rain drops depends on the drop size. Explained on this page:
http://www.madsci.org/posts/archives/2000-07/962626446.Ph.r.html

That page lists the speeds in meters per second, so we need to do some math.

60 seconds a minute and 60 minutes anhour works out to 260 seconds an hour.

And there are 1609.344 meters per mile.

So for the largest drop on chart, the terminal velocity is:
(3600 * 9.17) / 1609.344 = 20.5mph

So for the largest drops (assuming the chart only covers the largest to smallest sizes of rain drops), 20.5mph is terminal velocity.

But for the smallest size:
(3600 * 0.27) / 1609.344 = 0.6mph

If we further assume the average speed would be the average of those two speeds:

(20.5 + 0.6)/2 = 10.6mph.

So the average speed really does closely match the speed of the elevator on the Space Needle.

w00+! I love math (and wild assumptions)!