# Variations in Elastic Reversible Deformation

## Description

This is a basic physics tutorial that is targeted at GCSE (grade 9 and grade 10) standard reviewing Variations in Elastic Reversible Deformation. The video for this written tutorial is on its way.

## Variations in Elastic Reversible Deformation

Some elastic materials are more susceptible to deformation than others. That is, with the same force applied to them, they will deform more.

##### Object B deforms more than Object A with the same force applied. This means that Object B is more susceptible to deformation.

Moreover, the shape of an object can influence how much visible deformation occurs. For example, applying the same bending forces to a thick block of wood and a long thin plank of wood will result in varying degrees of visible elastic deformation. Because they're both made up of wood, they'll both exhibit elastic deformation within a certain force range - but the shape influences how visible this is.

## Yield Strength and Ultimate Strength

Materials that exhibit elastic deformation will only do so to a certain point. After this they'll start to undergo irreversible (permanent) deformation and/or break. For example, a plastic ruler will reversibly bend to a certain point; eventually though, the elastic deformation stops and it becomes permanent deformation i.e. the ruler is permanently deformed. The point at which the elastic deformation stops and permanent deformation starts is called the yield strength. Sometimes it can also be referred to as the elastic limit.

If you keep adding more force to the plastic ruler, it will eventually break. This point is called the ultimate strength. Sometimes it can also be referred to as the breaking point.

In the next tutorial we'll review how varying force strength will influence deformation.