How would you find the density of plasticine?

Answer 1

Roll the plasticine into a sphere and measure the diameter and use the formula for the volume of a sphere V=pi r^2, then weight the sphere to get the mass and use Density = Volume upon Mass.

Alternatively, use Archimedes' principle: 1) Weigh a piece of plasticine to get its mass. Very carefully fill a glass with water so full that it cannot contain one more drop of water. Immerse the plasticine in the glass, collecting the water that has run out of the full glass. The volume of the water is equal to the volume of the plasticine. Determine the volume of the water by either weighing it (density of pure water is 1 g per mL) or by accurately measuring the volume. Density = mass (g)/ volume (mL)

2) If you have a balance that can determine mass of an hanging object, first weigh your plasticine to determine its mass. Then attach it to string and take its mass hanging (the string also has mass). Then take its mass while the plasticine is just submersed in water. It will weigh less when submersed in water. The loss of mass when submersed is equal to the mass of water that has the same volume as the plasticine. (density of water is 1 g per mL) Now you can determine the volume of the plasticine since the mass lost in g equals the volume of water in mL. Density is the original mass divided by the volume.