## Hooke's law (my brain just reached it's elastic limit)

I was very daring and entered the intro to engineering class as my elective in my first year of highschool. It turns out that I am in over my head. I am always up for a challenge, so I am sticking with the course I am one of the 3 freshmen in the class. On the first day of class our teacher was introducing the class and brought up that we would have to use some trigonometry and other math that the freshmen have no learned yet but he is willing to help us out with that... Anyhow today at the end of class we were given a hand out about "hooke's law" because we had just done a lab where we attached weights to a spring. The paper is pretty straight forward about hooke's theory and the formula F= K (delta)L (Force = K times the change in length) it defines k as the "proportionality constant" which I do not understand. What is a proportionality constant? wikipedia says its a force or spring constant which I still do not understand. Wiki also gives the formula F= -K x (with arrows over the k and x). help please!

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kis, the more force it takes to extend a material by a given amount.It only holds for the first part of the graph you produced, when the line was straight. It is the gradient of the straight line.

(Sometimes the

kis a lambda)Kis N/m, or Newtons/meter.Does that help?

Yis proportional toX, that means that you can make a nice equation for the value ofYthat involvesXmultiplied by some constant number (without more complicated factors like powers, logarithms, etc.) The "proportionality constant" is just a fancy name for that constant. So in your classic algebraic equation for a line

you could callY= mX+ bmthe "proportionality constant" instead of the slope.Relating such constants to intuitive real-world characteristics can be challenging. As Kiteman says, for Hooke's law it's related to the stiffness or strength of the spring...