Answer:
The Archimedes Principle
Step-by-step explanation: He took the 5 kg crown and dipped it in a vessel full of water. He calculated the displaced water.
Then he took 5 kg pure gold bricks and dipped it in a vessel full of water. He then calculated the displaced water and he found that the vessel with pure gold bricks displaced more water than the vessel with the crown. This is the Archimedes principle which states that the body at rest in a fluid is acted upon by a force pushing upward called the buoyant force, which is equal to the weight of the fluid that the body displaces.
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