1

Physiology & Medicine / Why do finger nails grow so much faster than toe nails?

« on: 08/01/2010 09:29:39 »

I think it has a lot to do with temperature.  My toenails definitely grow faster in summer.  This fits with the blood supply answer above as in the cold blood flow will be reduced to the toes.

2

General Science / How much salt in seawater?

« on: 08/01/2010 09:23:18 »

I have been confusing two facts - admittedly I was told them at school over 20 years ago.
1) Seawater is indeed about the same salinity as 2 tablespoons of salt per quart. However it freezes around -2°C as stated above.
2) A saturated solution of saltwater freezes at -21°C (and would require over 10 times as much salt - nearly half a pound)

For you metric dudes  Seawater equivalent salinity is 35g Salt per litre
Saturated salt solution around 380g per litre.

So to answer my own question:
Assuming a straight line relationship between freezing point and amount of salt dissolved (and I am not certain of this)  I would need around 5 tablespoons of salt per quart to get a mixture that wouldn't freeze on my car windows until -10°C.

3

General Science / How much salt in seawater?

« on: 07/01/2010 16:11:45 »

One for a cold morning: I'd run out of de-icer, and the frost was really tough to scrape off.  When melting the ice off my car I thought if I just add a couple of tablespoons of salt to a quart of warm water - that should both melt the ice and prevent refreezing - as I think sea water freezes at -21°C, and its hardley ever that cold.

No - that wasn't enough salt - It soon refroze. 

What would the correct proportions of salt to water be to get that seawater -21°C freezing temperature?

4

General Science / Is this the secret to happiness?

« on: 07/01/2010 15:57:57 »

Right! its the doing thats important.

I've always thought of happiness as persuing a goal, which is difficult enough to keep you interested but easy enough so you don't give up.  Once the goal is achieved you get a few moments of satisfaction before looking for something else to do.  So you don't achieve happiness and that it - now you are happy - you have make your happiness by continually persuing interesting things to do.

5

Plant Sciences, Zoology & Evolution / Can anyone help identifying jelly like masses?

« on: 07/01/2010 15:21:25 »

Possibly some kind of bryozoan

http://www.deq.state.mi.us/documents/deq-ead-tas-bryozoan.pdf 

Was the stuff actually in Lake Michigan - deep water or a smaller shallow lake?

EDIT:  Try a google image search on 'bryozoans' - some look exactly like you described