Calculating Buoyant Force: Volume of a Raft Floating on Water

AI Thread Summary
To calculate the volume of a raft floating on water, first determine the mass of the raft using its density and surface area. With a density of 700 kg/m^3 and a surface area of 8.2 m^2, the mass can be calculated. The raft displaces a volume of water equal to its weight, which is based on the density of water at 1000 kg/m^3. By knowing that 75 cm of the raft is above water, the submerged height can be found by calculating the total volume and subtracting the volume above water. This approach allows for determining the submerged depth of the raft accurately.
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What is the volume of a raft floating on water with a surface area of 8.2 m^2 and density of 700 kg/m^2. 75 cm of the raft is above the water. The density of the water is 1000 kg/m^2.



ive tried B = pvg and m = pv and tried solving but nothing is working because i can't find the unknown height that is submerged in the water.

my other attempt was v = 8.2(.75 + x) but that really didnt get me anywhere
 
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Figure out the mass of the raft (you are given its density and size).
The raft will displace that same mass of water, so you can figure out the volume of water displaced and from there get the depth of the raft in the water.
 
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