Examples where derivatives are used (outside of math classes) I want to know what is the use of derivatives in our daily life. 
I have searched it on google but i haven't find any accurate answer. I think it is mostly used in Maths but I want to know its use in other departments i.e physics, chemistry, biology and economics.

All of the above.
It is actually easier to explain physics, chemistry, economonics, etc with calculus than without it.
For example:
Velocity is derivative of position with time.
Derivative of momentum (by time) is force.
Derivative of Gibbs free energy with number of atoms is chemical potential.
Etc.
I do honestly use calculus daily and I am not a mathematician.  Please feel free to add to this list.
