Question

What does the spring balance measure how would you demonstrate the principle on which it works

Answer 1

A spring balance is used to measure the weight of the body with in the elastic limits of its spring. Spring balance works on the principle of Hook's law. Hooke's law to say that the strain (deformation) of an elastic object or material is proportional to the stress applied to it.

Answer 2

Spring balance measure weight.
It work on the principal of Hooke's Law