Hooke's Law states that the distance a spring will stretch beyond its natural length varies directly with the force applied to the spring. A force of 12 pounds is needed to stretch a certain spring 9 inches beyond its natural length.

Question

Find a formula that models the length a spring will stretch beyond its natural length in inches as a function of the force applied to the string in pounds. (All I could figure out is that the input is the weight and the output is length. I don't know how to find the formula though, please help!!)

Answer 1

Just translate the English into Math ...

" the distance a spring will stretch ...varies directly with the force applied to the spring"
---> d = k(1/F) , where d is the distance, and F is the force
use the given: d= 9, F = 12

9 = k(1/12)
k = 108

thus d = 108/F

now wasn't that easy ?