James drops a wooden block into a tank of water and notices that it floats. He then cuts the block in half, drops the block into the same tank and once again the block floats. James realizes that cutting the block in half does not change its density. What type of property does James observe in his demonstration?

The property that James observed is the relative density of the object and hence the upthrust of a liquid which is explained by Archimedes principle

Explanation:

The pressure in a liquid exerts an upward force on an object placed in it. This is known as the buoyancy of the object in the liquid. The phenomenon was first explained by Archimedes, in a statement known as Archimedes' principle which states that the up thrust or buoyancy of an object is equivalent to the weight of fluid which it displaces.

conduction, convection, radiation