# Deformation of Solids

**Hooke’s law**

The amount by which an object is stretch is proportional to the amount
of force applied, assuming the elastic limit has not been exceeded. An
object stretched beyond its elastic limit will become permanently deformed.

Hooke’s Law (as long as the elastic limit has not been exceeded)

Force = Extension x Spring Constant

Spring Constant (Nm^{-1})

### Equations

#### Graphical Solutions

#### Elastic and plastic materials

#### Brittle and Ductile materials

#### Spring Combinations

Experiment to give the Young Modulus of a wire.

Note this is the only experiment that could be asked about in the exam.

**Measurements**

Diameter of wire

Micrometer in several places and an average used

**Length of wire **

Meter rule for a wire greater than 1 meter

**Mass **

Repeat on unloading as well as loading to ensure the material doesn’t
exceed its elastic limit

**Extension **

Vernier scale repeated on loading/unloading and a mean used

Calculations

The following will need to be calculated:

**Final step**

Plot a stress-Strain graph and draw a line of best fit. Calculate the
gradient using a tangent to give the Young Modulus.

**Reference Tools**

Dictionary

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Scientific Calculator

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Translator

Unit Conversion

**Module 1**

Useful Physics Resources

Scalars, Vectors & Graphs

Fundamental Equations and Complex Vector Equations

Equations of Motion

Moments

Pressure, Work, Energy and Power

Deformation of Solids

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