Question

A 42.5-kg boy uses a solid block of Styrofoam as a raft while fishing on a pond. The Styrofoam has an area of 1.4 m2 and is 0.055 0 m thick. While sitting on the surface of the raft, the boy finds that the raft just supports him so that the top of the raft is at the level of the pond. Determine the density of the Styrofoam. kg/m3

Answer 1

xo.oss) m Total ha (42.5kg xg9N. The volum of the Styrofoam Vs= (1140 choing) 1 Feb Vg=0.077 m3 Ler's take the ass mass of styrofan acting on the water = ns of the boy t ut. of strophen styrofoam. WI= 242.5+mg N. Now to float the by went buysent force. Fb = WT. Fo= ont of the water displaced by the styto toam. since the styrofoam is justaut water level, hence displaced (volume) water will be equalto volum of the styrofoan. Fb (vs x1000)*8. [ Take density of water = rookg/m3 (42.5+ m) Kg V sx 1000 xg 42-5+ m = 0-097 X1000 .. ma 34-5 kg. Mass of the styrofoam m= 34.5kg. volume of in V=0.077 m3 . : density of styro so foam d=m 448.052 kg/m3 . Vs ds=448.052 kg/m3