You can use it to measure force based on Hooke’s law.

When a force is applied, the spring stretches—the greater the force, the greater the extension.

To study this relationship, masses are added gradually, therefore increasing the force on the spring.

A graph of force vs. extension is plotted, and if all points lie on a straight line, it confirms Hooke’s law.

Write it as:

F = k × x,
where:
F is the applied force,
x is the extension of the spring,
k is the spring constant (a measure of stiffness).
You can use spring balances in physics labs to measure weight, verify Hooke’s law, and additionally understand the linear relationship between force and extension in elastic materials.