In: Physics
What is the smallest area of ice 29 cm thick that will support a 85 kg man? The ice is floating in freshwater.
Let be the volume of the ice
Density = Mass/Volume
Mass=Density*Volume
Weight = Mass*g
--------
So Weight of ice = Density of ice * Volume of ice* g
================
Weight of man,
=================
The buoyant force on ice must balance weight of ice and weight of man
Buoyant force = Density of fluid * Volume of displaced fluid*g
Let's assume that ice is completely submerged but it supports the man. In that case volume of displaced fluid is the same as the volume of ice.
Cancel g
-------
Volume = Area*Thickness
ANSWER:
===========================