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Both, elastic and plastic materials are widely applicable and used in the field of science and technology. Many of us wonder are elastic and plastic same. Thus, it is easier to understand these properties in terms of physics.
Let’s understand are elastic and plastic same and what is the difference between elastic and plastic.
What is Elastic?
When an external force is applied to a rigid body there is a change in its length, volume (or) shape. When external forces are removed the body tends to regain its original shape and size. Such a property of a body by virtue of which a body tends to regain its original shape (or) size when external forces are removed is called elasticity.
The objects that exhibit the elasticity property are known as elastic.
Some common examples of elastics are elastic waistbands, rubber bands, resistance bands, spring toys, spring mattresses, trampolines, and bows.
What is Plastic?
Plasticity is the ability of certain solids to flow or to change shape permanently when subjected to stresses of intermediate magnitude between those producing temporary deformation, or elastic behaviour, and those causing failure of the material, or rupture.
The substances that exhibit the plasticity property are known as plastics.
Some common examples of plastic are bottles, cups, spoons, etc.
Are Elastic And Plastic Same?
Generally, the terms ‘plastic’ and ‘elastic’ are physical properties, used to describe an object. They describe the attributes of materials such as rubber, plastic, metal, etc. In physics, when an external force is applied to the surface of any material or a body, the material undergoes a physical change or deformation. Now, when the force is removed, the material depending on its properties may or may not return to its original shape.
Now, if the body returns to its original shape, the body is said to be elastic in nature, and this property is called ‘elasticity’. On the other hand, if the body does regain its original shape, the body displays plastic nature, and this property is termed as ‘plasticity’. Based on the above explanation, it becomes easier to define the two properties, and state the difference between them.
The ‘elastic limit’ of a body is defined as the maximum extent to which a solid may be stretched without permanent deformation. This property can be easily explained on the basis of Hooke’s law. The law states that the elasticity of that material depends on the ratio of the stress and strain acting on the body.
It means, if the applied stress is linear or equal to the strain on the body, then the body is under an elastic limit and is elastic in nature. But, when the force or stress on the body increases and the elastic limit is broken, the body becomes deformed and turns plastic in nature. This limit is known as the yield strength of the material, wherein an elastic body turns plastic in nature.
Plasticity is defined as the ability of a body to change its shape and size permanently when an external force is applied. In a plastic body, when a force is applied, from the many layers of atoms, two of these layers slide from their crystal planes and lose their elastic limit, which causes deformation in the body.
Based on the above explanation, one can say that a change in these properties only happens, when a body undergoes elastic deformation to enter plastic deformation. Thus, it can be said that both these properties are interrelated.
Difference Between Elastic and Plastic
The main differences between elastic and platic are
| Criteria | Elastic | Plastic |
| Definition | The property on account of which a body regains its original size and shape on removal of external deforming force is called an elastic body. | The property on account of which a body does not regain its original size and shape on removal of applied force is called a plastic body. |
| Process | It is reversible. | It is irreversible. |
| Ductility | They are less ductile in nature. | They are highly ductile in nature. |
| Resilience | They have high yield strength. | They have low yield strength. |
| Modulus of elasticity (ratio) | The ratio of stress to strain is low or equal. | The ratio of stress to strain is high. |
| Toughness | They have the ability to absorb energy up to a fracture. | They do not have the ability to absorb energy up to a fracture. |
| Bonds | The molecular bonds do not get fractured. | The molecular bonds are fractured. |
| Shape and Size | The shape and size do not change permanently. | The shape and size change permanently. |
| Example | Rubber | Plasticine |
Practice Problems
- Are Plastic and Elastic the same?
- What is Plastic?
- What is Elastic?
- What is the difference between Elastic and Plastic?
FAQs
Is rubber elastic or plastic?
Rubber has elastic properties in varying degrees. Plastic, on the other hand, is not as elastic. It tends to deform when stretched, which is also known as necking.) As a whole class, complete a chart for plastics and rubber.
What material is elastic?
Elastic materials are types of materials that get back to their original shape after getting stretched by an external force. For example, rubber is an elastic material because it is stretched when force is applied to it but returns to its original shape once the forces are removed.
What is plasticity vs elasticity?
Elastic deformation or Elasticity is the deformation that subsides when the external forces that caused the change and the stress connected with it are removed. Plastic deformation or Plasticity is a persistent deformation or change in the shape of a solid body caused by a sustained force.
Conclusion
In our daily lives, we use different types of materials which are either elastic or plastic. The terms elasticity and plasticity are two different concepts. Elasticity is the deformation that subsides when the external forces that caused the change and the stress connected with it are removed, whereas plasticity is a persistent deformation or change in the shape of a solid body caused by a sustained force.
Recommended Reading
- What is PET – 7 Grades of Plastic
- Did You Know That There Are 5 North Poles?
- 12 Life Changing Discoveries And Inventions That Were Totally Accidental
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