Re: [Phys-L] Nice question on buoyancy and balance

["Anthony Lapinski" <Anthony_Lapinski@pds.org>]

Cool! Then, of course, you could make it an ice cube. What happens
to the water level (and scale reading) after the ice has melted?
Of course, neglect any evaporation effects, etc.

These are tough questions for kids, and some know that water
expands when it freezes.


Phys-L@Phys-L.org writes:
> > ie, tethering the previously floating ball to the floor does not 
> > affect the scale reading.
>
> The other nice question to add to this soln is:
>
> Say the right-hand beaker has no steel ball in it but has water up to 
> the same level as the left-hand beaker. Then what?
>
> Answer: The beam balances.
>
> In other words, the weight of a beaker full to level L is the same as 
> a beaker that has a ping-pong ball floating on its surface, if it is 
> filled to level L at its edges.
>
> ie. beakers |------|  and |--/\--| both have the same weight
>             |      |      |  \/  |
>             |      |      |      |
>             --------      --------
> -- 
> Carl E Mungan, Assoc Prof of Physics  410-293-6680 (O) -3729 (F)
> Naval Academy Stop 9c, 572C Holloway Rd, Annapolis MD 21402-1363
> mailto:mungan@usna.edu     http://usna.edu/Users/physics/mungan/
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