- #1

Trevorman

- 22

- 2

## Homework Statement

Brittle materials as glass and ceramics have generally a much lower tensile strength than compressive strength. A rigid mass impacts the end of a bar (free-free) of such a material and a piece of the other end drops off. Is there a relation between the length of the piece and the dynamic tensile strength of the material?

**Clarification**

A pressure wave is propagating through the rod, when the wave is reaching the free end at x = L, the wave reflects and becomes a tensile wave.

## Homework Equations

## \sigma =E \frac{\partial u}{\partial x} ##

E - Youngs modulus

##\sigma## - stress

u - displacement

## The Attempt at a Solution

Newtons second law

## \sigma_0 A - M * \frac{\partial^2 u }{\partial t^2}=0 ##

M - Mass of rod

##\frac{\partial^2 u }{\partial t^2}## -acceleration of the particles

## \sigma_0 ## - Initial stress

Don't really know how to tackle this problem and where to begin.