Question

Una barra de hierro cuya longitud inicial es de 2m se le incrementa su temperatura de 20 °C a 120 °C ¿Cuál es la longitud final de la barra? (considera que el coeficiente de dilatación del hierro) es 1,2 x 10-5 1/°C ( 3 puntos)

Answer 1

1.9976 m

Step-by-step explanation:

An iron bar whose initial length is 2m has its temperature increased from 20 ° C to 120 ° C. What is the final length of the bar? (consider that the coefficient of expansion of iron) is 1.2 x 10-5 1 / ° C (3 points)

Given that,

Initial length of an iron bar,
`L_0=2\ m`

The temperature increased from 20°C to 120°C

The coefficient of expansion of iron is
`1.2* 10^(-5)\ /^(\circ) C`

We need to find the final length of the bar.

The linear expansion equation is given by :

`\Delta L=\alpha L\Delta T`

Where
`\Delta L` is the change in length

`\Delta L=1.2* 10^(-5)* 2* (120-20)\\\\=0.0024\ m`

Also,
`\Delta L = L_o-L`

L is final length

`0.0024= 2-L\\\\L=2-0.0024\\\\=1.9976\ m`

So, the final length of the bar is 1.9976 m