Method 1: Weigh the mass m of the object with a balance; Fill the beaker with water, weigh the total mass m 1 with a balance, take out the object after it is immersed in water, and weigh the total mass m2 of the remaining water and beaker, with the mass of overflow water as the difference M 1-m2 and the volume of overflow water as the volume of the object; Find the density of an object.

Method 2: weigh the mass m of the object with a balance; Put a proper amount of water in the beaker, weigh the total mass with a balance, and hang the object in the water with iron wire (without touching the bottom of the container) to weigh the total mass m2. Then the difference between them is that the volume of boiling water is the volume of the object V = (m2-M 1)/ρ water, and the density of the object ρ=mρ water /(m2-M 1) is calculated.