Elasticity

Physics 202, Lecture 2

1

The three phases of matter are characterized by how they respond toexternal force

Physics 202, Lecture 2

2

As solids deform, they “push back” — this elasticity is often shown withsprings

Physics 202, Lecture 2

3

An ideal spring is the simplest elastic system and is defined by Hooke’sLaw

Physics 202, Lecture 2

4

Energy in an ideal spring is parabolic; the amplitude is tied to the totalenergy

Physics 202, Lecture 2

5

The forces need not be perfectly linear to apply these concepts: e.g., thependulum

Physics 202, Lecture 2

6

The deformation that results from small stress is linear (Hooke’s law again)

Physics 202, Lecture 2

7

Stress is from multiple forces on an object — can be classified as threebasic types

Physics 202, Lecture 2

8

Newton’s law of gravity creates stress on an astronomic scale: tides andgravity waves

Physics 202, Lecture 2

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