Eli5 How mathematicians figured out that they can link math to the real world?

Question

I still don’t understand how mathematicians use math in the real world and how they figure this out

In: Mathematics

Answer 1

Math works in the real world through the use of units. 1 = 1 in math. 1 carrot = 1 carrot works in the real world based on how you define a carrot. Carrots vary greatly in size so the equation works if you accept the units but may produce unexpected results – you could be saying a tiny carrot is equal to a large carrot.

With engineering, physics, chemistry, etc the key thing that makes them work is units. F=ma is not generically true. The units have to be correct. If you use F and m in metric units but acceleration in furlongs per fortnight your answer will be wrong.