To determine density we use volume and mass. Now he could determine the density of the crown. He found that the crown was a mixture of gold and silver and that the goldsmith had tried to cheat the king.
The crown and the gold nugget have equal weight
The crown displaces more water than the gold nugget
Archimedes did other experiments with buoyancy and fluids.
In object immersed in a fluid does not rise or sink if the amount of force pulling down (gravity) equals the amount of force pushing up (buoyancy).
Neutral buoyancy – when gravity equals buoyancy.
Archimedes’ principle – the buoyant force acting on an object equals the weight (force of gravity) of the fluid displaced by the object.
How Buoyancy and Density are Related
Buoyant forces depend on density. The more dense a fluid the more easily an object will float in it. If fluids have a different density the less dense one will float on the denser one.
Which is more dense, water or oil?
Hydrometer – used to measure the density of a liquid
Where would a hydrometer be used?
- determine if the antifreeze in a car is of the right mixture
- determine the sugar content of canned fruit syrup
content of alcohol in wine