In this video David quickly reviews the momentum and impulse topics on the AP Physics 1 exam and solves an example problem for each concept. Created by David SantoPietro.

This course discusses the fundamental material science behind amorphous solids, or non-crystalline materials. It covers formation of amorphous solids; amorphous structures and their electrical and optical properties; and characterization methods and technical applications.

In this math activity, students conduct a strength test using modeling clay, creating their own stress vs. strain graphs, which they compare to typical steel and concrete graphs. They learn the difference between brittle and ductile materials and how understanding the strength of materials, especially steel and concrete, is important for engineers who design bridges and structures.

This course reviews the processing and structure of cellular materials as they are created from polymers, metals, ceramics, glasses, and composites, develops models for the mechanical behavior of cellular solids, and shows how the unique properties of honeycombs and foams are exploited in applications such as lightweight structural panels, energy absorption devices and thermal insulation. The applications of cellular solids in medicine include increased fracture risk due to trabecular bone loss in patients with osteoporosis, the development of metal foam coatings for orthopaedic implants, and designing porous scaffolds for tissue engineering that mimic the extracellular matrix. Modelling of cellular materials applied to natural materials and biomimicking is explored. Students taking the graduate version of the class are required to complete additional assignments.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Adaptability gives species an edge in surviving environmental changes both big and small But how different species adapt together isn’t always clear For instance, how do predator and prey adjust their interactive behavior in the face of climate change? A new predator-prey model provides some clues Researchers looked at how tweaks to offensive and defensive strategies affected predator-prey populations under two types of disturbances -- Short-term perturbations, such as extreme weather events And permanent perturbations, such as climate change They found that fast adaptation can hold population dynamics steady against these disturbances But in some cases, adaptation can worsen the effects of perturbations This finding suggests that understanding perturbation type, target, and strength matters -- Strengthening the need for tailored approaches to ecosystem management in changing environments Raatz et al..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

Investigate collisions on an air hockey table. Set up your own experiments: vary the number of discs, masses and initial conditions. Is momentum conserved? Is kinetic energy conserved? Vary the elasticity and see what happens.

16.225 is a graduate level course on Computational Mechanics of Materials. The primary focus of this course is on the teaching of state-of-the-art numerical methods for the analysis of the nonlinear continuum response of materials. The range of material behavior considered in this course includes: linear and finite deformation elasticity, inelasticity and dynamics. Numerical formulation and algorithms include: variational formulation and variational constitutive updates, finite element discretization, error estimation, constrained problems, time integration algorithms and convergence analysis. There is a strong emphasis on the (parallel) computer implementation of algorithms in programming assignments. The application to real engineering applications and problems in engineering science is stressed throughout the course.

An interesting case of price elasticity of demand is a demand curve with a constant unit elasticity. Explore what such a demand curve would look like in this video. Created by Sal Khan.

Price of one good impacting quantity demanded of another. Created by Sal Khan.

Walk through the logic of determining what kind of good has the most elastic demand in this video.

There are several factors that affect how elastic (or inelastic) the price elasticity of demand is, such as the availability of substitutes, the timeframe, the share of income, whether a good is a luxury vs. a necessity, and how narrowly the market is defined. We explore each of these in this video.

Following the steps of the iterative engineering design process, student teams use what they learned in the previous lessons and activity in this unit to research and choose materials for their model heart valves and test those materials to compare their properties to known properties of real heart valve tissues. Once testing is complete, they choose final materials and design and construct prototype valve models, then test them and evaluate their data. Based on their evaluations, students consider how they might redesign their models for improvement and then change some aspect of their models and retest aiming to design optimal heart valve models as solutions to the unit's overarching design challenge. They conclude by presenting for client review, in both verbal and written portfolio/report formats, summaries and descriptions of their final products with supporting data.

David explains what it means for a collision to be elastic or inelastic. Created by David SantoPietro.

Animated PowerPoint's originally created to assist deaf students to learn the concept and math of Elasticity of Demand.  

As part of the engineering design process to create testable model heart valves, students learn about the forces at play in the human body to open and close aortic valves. They learn about blood flow forces, elasticity, stress, strain, valve structure and tissue properties, and Young's modulus, including laminar and oscillatory flow, stress vs. strain relationship and how to calculate Young's modulus. They complete some practice problems that use the equations learned in the lesson mathematical functions that relate to the functioning of the human heart. With this understanding, students are ready for the associated activity, during which they research and test materials and incorporate the most suitable to design, build and test their own prototype model heart valves.

Why we calculate percent changes in a strange way when calculating elasticities. Created by Sal Khan.

Sal graphs elastic potential energy and kinetic energy for a mass on a spring and compares the total energy when with and without dissipative forces (friction).

This subject provides an introduction to the mechanics of materials and structures. You will be introduced to and become familiar with all relevant physical properties and fundamental laws governing the behavior of materials and structures and you will learn how to solve a variety of problems of interest to civil and environmental engineers. While there will be a chance for you to put your mathematical skills obtained in 18.01, 18.02, and eventually 18.03 to use in this subject, the emphasis is on the physical understanding of why a material or structure behaves the way it does in the engineering design of materials and structures.