Ice and water

[_anant]

source:british physics olympiad
a beaker of water has a piece of ice floating on its surface.When the ice melts,show that (by logic or by equations)
1.that the water level remains unchanged.
2.If a coin was initially kept above the ice block what chang will be there in answer to 1?
:tongue2: 3.if the ice piece initially had an air cavity inside it how will the answer change?
:tongue2: 4.if there is a miscible liquid TRAPPED inside the cavity then what will happen to the level of the water?

 

[Saketh]

Think about the volume of water that was displaced before the ice melts, and the volume of water that was added after the ice melts (no more displacement).

Once you figure this out, all the other situations are just variations on the simple theme.

 

[DaveC426913]

This has been answered elesewhere. Here's a diagram for Part 1: