Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Ranjit on 19/01/2011 23:30:03

Title: Why does a lemon float in salty, but not fresh water?
Post by: Ranjit on 19/01/2011 23:30:03

Ranjit asked the Naked Scientists:
   
Why does a lemon float in salt water but not in drinking water?

What do you think?

Title: Why does a lemon float in salty, but not fresh water?
Post by: Soul Surfer on 19/01/2011 23:35:34

Salt water is slightly denser than fresh water.  so presumably a typical lemon is less dense than salt water and more dense than fresh water.

A similar effect happens with eggs and fresh water.  As an egg ages so the bubble of gas in the end increases.  New laid eggs sink, eggs a few days old tip up and stand on end at the bottom of the jar and if an egg floats, it is rather old.  if it floats high in the water it is probably bad.