Explain Linear expansion and derive Co-efficient …

Linear Expansion means expansion in length due to increase in temperature. Linear expansion means fractional change in length i.e. how the length is changing with respect to original length.

As we can seefrom above images the length has been increased from

l to l+Δl.                                              

Coefficient of Linear Expansion is a parameter which tells us how the size of the object changes with change in temperature. It is defined as degree of linear expansion divided by the change in temperature.

• If the solid is in the form of long rod, then for small change in temperature, ΔT, the fractional change in length, Δl/l, is directly proportional to ΔT.

Mathematically can be written as:-

Where α_l= the coefficient of linear expansion

It is denoted by α_l

• It is characteristic of the material of the rod.It varies for different substance.