Question

An object weighing 299 N in air is immersed in water after being tied to a string connected to a balance. The scale now reads 260 N . Immersed in oil, the object appears to weigh 273 N . Find the density of the object. Answer in units of kg/m3 .

Answer 1

Answer:

7666.67 kg/m³

Explanation:

Density of water = 1000 kg/m³

g = Acceleration due to gravity = 9.81 m/s²

V = Volume

Weight of the water displaced

$299-260=39\ N$

The buoyant force

$F_B=\rho Vg\\\Rightarrow 39=1000V\times 9.81\\\Rightarrow V=\dfrac{39}{1000\times 9.81}\\\Rightarrow V=0.00397\ m^3$

Density is given by

$\rho=\dfrac{m}{V}\\\Rightarrow \rho=\dfrac{\dfrac{299}{9.81}}{\dfrac{39}{1000\times 9.81}}\\\Rightarrow \rho=7666.67\ kg/m^3$

The density of the object is 7666.67 kg/m³