A raft is made of 9 logs lashed together. Each is 29.1 cm in diameter and has a length of 5.7 m. How many people can the raft hold before they start getting their feet wet. Assume the average person has a mass of 69.3 kg and that the density of water and wood is 1000 kg/m3 and 600 kg/m3, respectively(adsbygoogle = window.adsbygoogle || []).push({});

[okay, what i did was i found the volume of one log.

V = (pi)(r^2)H

r is used 0.1455 (29.1 converted to m then divided by 2 to get radius)

h i used 5.7m , then times it by 9.

(i got an answer of 3.411875)

then i found FB. FB = pwaterVg (1000)(3.41188)(9.81)

since i knew the density of wood, and the volume, i found the mass

m = pwoodV

got an answer of 2047.125

then i used this equation FB = [ x*mass of one person + mass of 9 logs] g

when im done, i get an answer of 46 people. its wrong. can someone show me where im going wrong!?

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# Homework Help: 9 logs, how many people?

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