Physics - Elasticity and Density
Elasticity
If an object is subjected to a stress and it therefore undergoes strain, it changes shape. Now suppose the stress is removed, some objects will return to their original shapes and some will not. The ones that do are said to be elastic and the ones that do not are said not to be elastic. All substances that obey Hooke’s Law are elastic.
Density
Every substance has a density. A substance’s density is the number of kilograms contained in one liter of the substance.
Rule number 20: Definition of Density
Density equals mass divided by volume. You should also know about specific gravity. The specific gravity for any substance is the density of the substance divided by the density of water. Remember, that the density of water is 1000 grams per liter.
If an object is subjected to a stress and it therefore undergoes strain, it changes shape. Now suppose the stress is removed, some objects will return to their original shapes and some will not. The ones that do are said to be elastic and the ones that do not are said not to be elastic. All substances that obey Hooke’s Law are elastic.
Density
Every substance has a density. A substance’s density is the number of kilograms contained in one liter of the substance.
Rule number 20: Definition of Density
Density equals mass divided by volume. You should also know about specific gravity. The specific gravity for any substance is the density of the substance divided by the density of water. Remember, that the density of water is 1000 grams per liter.
