Naked Science Forum

General Science => General Science => Topic started by: John on 12/09/2010 14:30:02

Title: Why doesn't a teabag cause the water level to rise?
Post by: John on 12/09/2010 14:30:02

John asked the Naked Scientists:
   
Hi, 

When I fill a mug with boiling water to a certain level and place a teabag in it, the teabag floats, slowly absorbs water and then sinks to the bottom.  I would expect the level of water to rise slightly as the absorbent teabag still adds volume to the cup, but in reality, the water level drops slightly.

Could you explain this?

What do you think?

Title: Why doesn't a teabag cause the water level to rise?
Post by: tommya300 on 12/09/2010 15:53:26

The dry material and the bag absorbs aprox the same amount of the the water that it may displace. The system does not add any water that is already there.
Try force submerging the bag and see what happens, you will see a slight rise as the bag and tea absorb the water the level drops.
 Zen master would say, "making the tea, one, with the water!"
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