Question: what is Hooks law?

Robert Woolfson answered on 20 Jun 2013:

Hookes law is about how hard it is to stretch springs (and objects that act like springs). Say you have a spring, and you want to find out how stiff it is. You pull it and get a rough idea. Hookes law allows you to get an exact number. The law is:

F=kx

F is a symbol for force, meaning how much effort are you putting in to something (sort of). k is a symbol that describes how stiff the spring is, called the spring constant. x is the symbol for distance moved.

All this formula says is that if you measure how much force you use to stretch a spring, and how far the spring stretches, you can work out exactly how stiff your spring is.

While this sounds very physicsy (which it is), it comes up in chemistry and biology as a lot of things act like springs. For example, one way of describing the bonds between atoms in a molecule is as springs. Using a slightly different version of the equation above, we can work out how strong the bond is which is very useful to us.