Area Expansivity

When substances are heated, there is an increase in length, breadth and height, hence area and volume also increases.

An increase in area of a solid when heated is called area or superficial expansivity.

Therefore;

Area Expansivity = β

\(\scriptsize (β) = \normalsize \frac {Increase \: in \: Area}{Original \: Area \: \times \: Temperature \: Change}\) 

  \(\scriptsize β = \normalsize \frac {A_2 \: - \: A_1}{A_1 \: \times \: (\theta_2 \: - \: \theta_1)}\) 

• A₂ = New area
• A₁ = Initial/Original area
• θ₂ =