Question

1. A sheet of brass is 50 cm long and 10 cm broad at 0°C. Thearea of the surface increases by 1.9 cmat 100°C. Find the
coefficient of linear expansion of brass.​

Answer 1

Answer:

$\sf \alpha =1.9\times10^{-5} \ / C$

Explanation:

Given :

$\sf S_0=50\times10 \ cm^2$

$\sf S_0=500 \ cm^2$

$\sf \Delta S=1.9 \ cm^2$

$\sf \Delta T=100 \ C$

We are asked to find coefficient of linear expansion i.e. $\sf \alpha$

We know :

$\sf \beta = \dfrac{\Delta S}{S \ \Delta T}$

Putting values here we get :

$\sf \beta = \dfrac{1.9}{500\times100} \ / C$

$\sf \beta =3.8\times10^{-5} \ / C$

But :

$\sf \alpha = \dfrac{\beta }{2}$

$\sf \alpha =\dfrac{3.8\times10^{-5} \ / C}{2}$

$\sf \alpha =1.9\times10^{-5} \ / C$

Therefore we answer.