Question

A solid of mass 1.3kg,suspended by a string is completely in water. If the tension in the string is 6N,calculate
a)the upthrust on the solid
b)the volume of the solid
c)it's density(density of water is 1000kgm

Answer 1

Please help me find the solution

Answer 2

weight = 1.3 kg * g = 1.3*9.81 = 12.8 Newtons
force up from string = 6 Newtons
so weight of water displaced = 12.8 - 6 = 6.8 Newtons (says Archimedes)
That 6.8 is the upthrust (buoyancy)
volume = mass of water displaced / density = (6.8 / 9.81) /1000 kg/m^3 = 0.693*10^-3 meters^3
density = mass/volume = 1.3 kg / (.693*10^-3) = 1896 kg/m^3
about 1.9 times water density