Tension in an elastic string

Question

gorica · Answer

Natural length of a string is a, coefficient of flexibility is λ. I have found that tension in string is $$S=-\lambda \frac{(x-a)}{a}$$ where $$(x-a)$$is extension. Is this formula or it has to be calculated somehow?

gorica · Answer

I think I should have ask this in physics :D

ankit042 · Answer

I think this equation is from some standard law (Hook's not sure though)

gorica · Answer

I think it's Hook's too, but I am not sure if I will have to give an explanation for how did I get it or I can consider it as a formula.

ankit042 · Answer

I think it is a standard formula you can directly use it (something like F=ma). 
I use to use F=-kx .

gorica · Answer

I've just found that $$k=\frac{\lambda}{a}$$ where k is stiffness and λ is coefficient of flexibility. That's how they got S :)