Question

why are si units professed over non standard units of measurement

Answer 1

Consider an instance where you call an apple with the name 'apple' and the other guy from some other country calls it something else.Similarly,everybody calls it something in their own language.In case you guys meet up sometime,and somehow a conversation about apples strikes up,how do you think you would all be able to understand what the other person is talking about?What I am trying to say that if someone goes on calling something with different names,there would be a lot of confusion.Hence to avoid this confusion,the SI system was adopted.Therefore,they are professed so as to maintain uniformity and avoid confusion.Hope this helps :)