Question

A blacksmith heated a metal whose cubic expansivity is 6.3×10^-6K^-1.The area expansivity is?

Answer 1

4.2 X 10⁻⁶ K⁻¹

Step-by-step explanation

The three common expansivities we usually have are linear, area and cubic:

`\begin{gathered} \text{linear }=\alpha \\ \text{ area }\beta=2\alpha \\ \text{ cubic }\gamma=3\alpha \end{gathered}`

If we have to cubic expansivity, we can find the linear by dividing by 3:

`\alpha=(\gamma)/(3)=(6.3*10^(-6))/(3)=2.1*10^(-6)`

And then find the area expansivity by multiplying by 2:

`\beta=2\alpha=2\cdot2.1*10^(-6)=4.2*10^(-6)`