Question

A sheet of glass measures one metre by half metre at 0°C. Calculate its area at 30°C, a for

glass = 0.000009°C-1.
​

Answer 1

0.50027
`m^(2)`

Step-by-step explanation:

ΔA=
`2\alpha A_(0) T`

Where ΔA is the change in area

There is a 2 since the coefficient for area = 2 x that for the linear coefficient

`A_(0)` is the original area

`\alpha` is the coefficient of thermal expansion

And T is the change in temperature

ΔA=2(0.000009)(0.5)(30-0)=0.00027
`m^(2)`

New area= ΔA+
`A_(0)` = 0.5+0.00027=0.50027
`m^(2)`