Q13 of 292 Page 469

If the length of a simple pendulum is decreased by 2%, find the percentage decrease in its period T, where .


The formula for time period -


∴


Here 2,π,g have no dimensions. So we can eliminate them.


Now


By representing in percentage error


⇒


⇒


⇒


⇒


Hence the time period becomes 1 %.


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