(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A block of foam plastic has a volume of 25.0 cm^3 and a density of 0.800 g/cm^3. How large a force is required to hold it under water?

2. Relevant equations

F=mg, m=density times volume

3. The attempt at a solution

I first converted 25.0 cm^3 into 2.5 times 10^-5m^3 and .800 g/cm^3 into 800 kg/m^3

Then I used the formula m=density times volume

m=(density)(volume)

m=(800 kg/m^3)(2.5 times 10^-5 m^3)

m=0.02 kg

Then I used the formula F=mg and plugged 0.02 kg for the mass and 9.80 m/s^2 as g and multiply them together to get 0.196N but Ik the answer is suppose to be .0490 and Idk what I'm doing wrong can someone help me. Maybe I didn't think about the density of water or something like that

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# Homework Help: Pressure, Buoyant Force

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