We present the results of experiments on impact craters formed by dropping a steel ball vertically into a container of small glass beads. As the energy of impact increases, we observe a progression of crater morphologies analogous to that seen in craters on the moon. We find that both the diameter and the depth of the craters are proportional to the 1/4 power of the energy. The ratio of crater diameter to rim-to-floor depth is constant for low-energy impacts, but increases at higher energy, similar to what is observed for lunar craters.

We study the penetration of steel spheres dropped vertically into a container of loosely packed, small glass beads. We find that the penetration depth of the spheres increases linearly with the incident momentum of the projectile, but with a zero-momentum intercept that can be either positive or negative. This behavior can be understood by modelling the granular medium as a non-Newtonian fluid with a yield stress and an effective viscosity. We derive the scaling behavior of the viscosity and find agreement with our experimental results. PACS Nos.: 45.70.–n, 83.80.Fg, 47.50.+d

In recent years, the child welfare system has begun to focus on the overall outcomes of children by looking at overall well-being factors. However, despite this shift by social service practitioners, child protection courts have failed to similarly shift focus onto the long-term outcomes of children and remain focused only on legal permanency. This failure to recognize the importance of overall outcomes and other forms of permanency, such as relational permanence, on the future of system-involved youth can have devastating consequences. This article argues that child protection courts should integrate well-being indicators similar to problem-solving courts in order to have a greater influence on the overall outcome of these children. Key Points for the Family Court Community:• Identifies the importance of well-being indicators and discusses the need for the child welfare system to focus on overall outcomes of children • Addresses a gap between social service practitioners and the child protection court on working towards overall well-being • Educates child protection court and other child welfare actors on the different forms of permanence affecting systeminvolved youth • Discusses therapeutic jurisprudence and how this theory is integrated into problem-solving courts • Offers suggestion for how to integrate well-being indicators into child protection courts