Deformation
When a A push or a pull. The unit of force is the newton (N). acts on an object, the object may change shape by bending, stretching or compressing - or a combination of all three shape changes. However, to change the shape of a stationary object there must be more than one force acting to do one of the following.
Bend an object's ends past each other, eg when an archer pulls an arrow back against a bow.
Pull an object's ends apart, eg when a rubber band is stretched.
Push an object's ends together, eg when an empty drinks can is squashed.
A change in shape is called Changing shape and/or size as a result of forces being applied.:
- Elastic materials return to their original shape and size after being stretched or squashed. deformation is reversed when the force is removed
- A plastic material does not return to its original shape after being stretched or squashed. deformation is not fully reversed when the force is removed - there is a permanent change in shape
A rubber band undergoes elastic deformation when stretched a little. A metal drinks can undergoes plastic deformation when it is squashed.
Learn more on forces and elasticity in this podcast
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