Question

A 0.1m long elastic band extends 5mm when a load of 80N is hung from its end. Calculate the strain on the band

Answer 1

We can find the strain on the band from the formula:

$$\epsilon = \dfrac{\Delta l}{l_0} = \dfrac{l - l_0}{l_0},$$

here, $\Delta l$ is the extension of the band (or change in the length of the band), $l_0$ is the initial length of a band being stretched and $l$ is the length of the band after it has been stretched.

Then, we get:

$$\epsilon = \dfrac{(0.1 m + 0.005 m) - 0.1 m}{0.1 m} = 0.05.$$

Answer:

$\epsilon = 0.05.$