Understanding how materials behave when a force is applied is essential when engineers design the world around us. By considering how a simple spring behaves we then extend these ideas to investigate material properties.
Stretch a spring, or a piece of metal, and it gets longer. This relationship is explained in this video, along with a method of investigating the behaviour of materials to produce a force-extension graph.
Springs in Parallel and Series
If you understand how one spring extends when a load is applied you can then extend this knowledge to investigate combinations of springs in parallel and series. This also has many similarities to the way that combinations of capacitors behave when in a circuit.
Elastic Potential Energy in Springs
Stretch a spring, or a rubber band, and it stores energy. This is because work is done in extending it. This video explains how to calculate the amount of energy stored.
Stress, Strain and Young's Modulus
When revising for your exams it may seem like you are under stress and strain, however, they are quite different but they do allow to investigate materials. Their ratio can also be calculated giving the Young's, or Engineering, modulus.
This video explores the four key points you would expect to see on a stress-strain graph for a typical ductile material.
Ductile and Brittle Materials
A short video that explain the various material properties you need to understand and identify from a stress-strain graph. From brittle substances like glass and a Crunchie to the plastic deformation of copper and a Mars bar.
Behaviour of Rubber
Stretch a rubber band and it doesn't behave in the same way as a metal. As it is loaded and unloaded energy is stored which then causes the rubber to heat up.