Question

A 20g weight causes an extension of 0.72 cm in a spring. Calculate the extension caused by a load of 80g weight, assuming Hooke’s law is obeyed.? *

Answer 1

The Hooke’s law says

$$F=kx$$

Hence

$$\frac{F_2}{F_1}=\frac{x_2}{x_1}$$

$$x_2=\frac{F_2}{F_1}x_1=\frac{m_2g}{m_1g}x_1=\frac{80}{20}\times 0.72\:\rm cm=2.88 \:cm$$