The presentation discusses elasticity, defined as the ability of a deformed material to return to its original shape after deformation. It covers concepts such as Young's modulus, which relates stress and strain, and Poisson's ratio, defining the relationship between lateral and linear strains. The presenter explains different types of strain and properties of elastic and inelastic materials, using examples like springs and rubber bands.

1. Welcome to My
Presentation

2. My Topic is
Elasticity
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3. What is Elasticity ??
• The ability of a deformed material body
to return its original shape and size when
the forces causing the deformation are
removed is called elasticity
Rubber Band
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4. Elastic Properties of Matter
•An elastic body is one that returns
to its original shape after a
deformation.
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5. Elastic Properties of Matter
•An inelastic body is one that does
not return to its original shape after
a deformation
Inelastic Ball
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6. An Elastic Spring
• A spring is an example of an
elastic body that can be
deformed by stretching.
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7. Stress
The internal force of restitution per unit area of deformed body
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8. Strain
• It is the ratio of change in configuration to the
original configuration of the deformed body. It has
neither unit nor dimension.
• 1 ) Tensile Strain
• 2 ) Volumetric Strain
• 3 ) Shear Strain
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9. Youngs Modulus
• It is the ratio of longitudinal stress to the
longitudinal strain.
• Young’s modulus = longitudinal stress / longitudinal strain
• Y = ( FL ) / ( ΔLπr2)
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10. • “Within the elastic
limit the stress is
directly proportional
to the strain”.
• Stress ∝ strain
Hook’s Law
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11. Poisson’s Ratio
• Within the elastic limit, the
ratio between lateral strain
and linear strain is a constant.
This constant is called as
poisson’s ratio. It is
represented by 𝝈.
• 𝝈 = lateral strain / linear strain
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12. ANY QUESTIONS??
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13. THANK YOU
EVERYBODY
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