Lesson 15 Lesson 15. Floating or sinking- the role of weight.
Lets take several objects.
This leads to a problem, heaviness vs. lightness is very subjective. One person's heavy is another person's light. It becomes clearer when we directly compare objects. So we want to use a way that lets everyone decide know something about how heavy an object is. For this reason we use a scale where how much an object pushes down on a metal plate is compared with pieces of metal hung on an arm.