Question

Why does spring balance show wrong readings after long use?

Answer 1

Hint: When a spring balance has been utilized for a long time, it evolves elastic fatigue; the spring of such a balance needs a longer time to reach its original configuration. Therefore, it does not provide a correct measurement. In simple words, due to continuous usage, the wire dissipates its elasticity and does not recover its original arrangement that’s why it presents wrong readings.

Complete answer:
The spring is an illustration of the restraining force and its mechanism. Spring operates on the elasticity principle. A spring balance estimates the weight of an object by reversing the force of gravity, working with the force of a stretching spring. It may be utilized to discover mass as well as weight by recalibrating the rule. Some spring balances are available in gram or kilogram showings and are used to estimate the object's mass.
When the spring balances have been utilized for a long time, they acquire elastic fatigue in them. The elastic fatigue can be described as the property of the element that loses its power under the operation of the recurrent deforming and the restoring force.
Therefore, spring holds a spring constant and is implemented by force, extending itself to a distance. As soon as the force is discharged, the length gained is vanishing, and it comes back to its initial position. The same happens in spring balance; on inserting the weight, spring stretches, and eliminating the weight, the spring reverts to its primary position.
Following prolonged use, the spring's elasticity is lost or begins to lose. Therefore, the length extended is never retrieved to its initial position, and thus, the spring balance begins to give wrong measures.

Note: Elastic fatigue occurs when a body is governed by repeated strains or distorting forces, even by elastic boundaries. Under such conditions, a body dissipates its feature of elasticity. It is a characteristic of the elastic body by which its function becomes elastic under reoccurred alternating deforming force.