Question

A light unstretched/uncompressed spring with spring constant k = 80 N/m  rests vertically on the bottom of a beaker that contains an unkown fluid (Figure 1). A block of wood with mass m = 4 kg  and density ρ = 350 kg/m3  is connected to the spring. When the spring-block system reaches static equilibrium, the spring is stretched by a distance d = 0.3 m . Determine the density of the fluid?

Answer 1