20160320 Rainy days in March

We had a thaw and some rain a few days ago.  Here are some of the scenes we saw:

Little cobwebs stray from this tip of a juniper bush …

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See the globules of water resting in the cups of these Crowned Pixie Cups ?

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I wonder why these spheres cling to the spikes of these spore capsules????

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Rain “sticking” to the remnants of this inflorescence in the streaking rain.  Those streaks are about 4 cm long.  The camera exposure was 1/200 sec.  What is the terminal velocity of raindrops this size?

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Yes, about 800 cm/sec or 8 m/sec or about 29 km/hr or about 19 mph.

Do big raindrops fall faster or slower than little raindrops?

“Don’t try to balance on one leg when standing on ice!”  nags one to the other in the rain.

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PS  Big raindrops and little raindrops DO NOT FALL at the same speed …. in spite of what you might remember from high school physics.   Think of your experience in a thunderstorm compared to a Scottish mist rainy day.

Careful observation is often better than what is taught by folks who do not include the assumptions that are made in their promulgations!

Fortunately there are many teachers who get it right …. including this wonderful editor of his students’ work:

Speed of falling raindrops

I have bookmarked Glenn Elert’s Textbook, mainly because it is elegant and correct.  At least the parts that I read fit that description.  A nice find.

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