Physics

Problem

A cylindrical buoy has a volume of

0.40\,\text{m}^{3}

and unknown mass. It floats upright in river water (

\rho=1000\,\text{kg}\,\text{m}^{-3}

). When an additional

200\,\text{N}

load is placed on top, the buoy just submerges so that its upper surface is level with the water. Taking

g=9.8\,\text{m}\,\text{s}^{-2}

, what is the mass of the unloaded buoy? a)

200\,\text{kg}

420\,\text{kg}

380\,\text{kg}

400\,\text{kg}