posted by chibi .
David builds a wood raft that weighs 100lbs (445 N). The bottom area of the raft is 4 meters and by 3 meters and the raft is 0.6 meters thick. When the raft is floats in water, what must the height of the water line be on the raft?
ρ•V₁•g = Weight
ρ•x•y•z₁•g = Weight
z₁=Weight/ ρ•x•y•g =
=445/1000•4•3•9.8=0.0038 m =3.8 mm