Question

An object made of a single atomic element weighs 2.6000 N in air and 1.6370 N when completely submerged in water.

1. Calculate the density of the object.

2. What is the chemical symbol of the atomic element?

Answer 1

1.

The weight of the object in air is

where p is the density of the object and V is the volume of the object.

The weight of the object in water is

F_{​​​​​​B} is the buoyant force on the object in water, p_{​​​​​​w}​​​​​ is the density of the water.

Dividing the two weights

2.

The density is approximately 2700 kg/m^{​​​​​​3}​​​​​ which is the density of Aluminium. The chemical symbol is Al.