Final answer:
The purpose of measuring the density of a block in water in a physics lab report is to determine its density and understand how mass and density are related. The water displacement method is used to measure the volume of the block, and the density can be calculated by dividing the mass by the volume.
Step-by-step explanation:
The purpose of measuring the density of a block in water in a physics lab report is to determine its density. Density is a measure of how much mass is contained within a given volume. By measuring the mass and volume of the block in water, you can calculate its density using the formula: density = mass / volume.
In the lab, the water displacement method is used to measure the volume of the block. This involves placing the block in water and seeing how much the water level rises. The difference in water level before and after the block is submerged gives you the volume of the block.
The density of the block can then be calculated by dividing its mass by its volume. This allows you to compare the densities of different materials and understand how mass and density are related for blocks of the same volume.