Here's a cooking tip for asparagus. To know that you're getting only the tender part of the asparagus, apply physics by determining the "bending moment" (?) of the asparagus. How does one do that?
The first thing to remember about asparagus is that it is actually a tender shoot that was in the active and rapid process of turning itself into a woody stem before it was picked. The bottom part was already well on the way through the process, while the top part was still actively growing and is quite tender. From a materials perspective, those two parts have drastically different properties. The woody part is tough and resistant to breaking. It has the ability to bend a little without snapping, but is stiff enough to resist the bending. The tender, upper part is brittle and snaps easily. Most importantly, the tough part is able to withstand shear forces while the upper part cannot.
The only trick is to apply your forces correctly so that the maximum shear stress appears at the woody end of the asparagus and the minimum shear stress appears at the tender end. If you do it the wrong way, you’ll just break off the tip. So grip the tip in one hand, about an inch from the end. With your other hand grip the other end of the asparagus as close to the cut as you can. Hold the tip steady in one hand and bend the cut end, making sure that the axis of rotation is between your index finger and thumb. The asparagus will snap right at the junction between tender and woody.
Physics, and food. What could be a better combination? Well.... maybe physics and Disney, but that's another blog! :)