Question

Can I please get help on how to workout this problem?

9. You need to determine the density of a ceramic statue. If you suspend it from a spring scale, the scale reads 39.8 N. You then lower the statue into a tub of water, so that it is completely submerged, and the scale reads 11.4 N. a) What is the buoyant force acting on the statue? b) What is the volume of the statue? c) What is the density of the statue?

Answer 1

a. The buoyant force causes the decrease in weight so the buoyant force equal to change in weight = 39.8-11.4= 28.4 N

b. Fb= Vs × D × g, where Fb is the buoyancy force that is acting on the object, Vs is the submerged volume of the object, D is the density of the fluid the object is submerged in, and g is the force of gravity

Fb=28.4N, D = 1kG/ L, g = 9.8

Vs = Fb/ (D×g ) = 2.897 m3

C. Density = mass per volume  

Mass = W / g = 39.8/9.8 =4.06 Kg  

Volume =2.897 m3

Density = 1.359 kg / L