Question
Assertion : Spring balances show correct readings even after they had been used for a long time interval.
Reason : On using for long time, spring balances losses its elastic strength.

Answer

(e) When a spring balance has been used for a long time, the spring in the balance fatigued and there is loss of strength of the spring. In such a case, the extension in the spring is more for a given load and hence the balance gives wrong readings.

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