If the time period of oscillation of a pendulum is measured as 2.5 second using a stop watch with the least count (1)/(2) second, then the permissible error in the measurement is

If the time period of oscillation of a pendulum is measured as 2.5 sec

1.	If the time period of oscillation of a pendulum is measured as 2.5 second using a stop watch with the least count (1)/(2) second, then the permissible error in the measurement is
Answer» `10%` `30%` `15%` `20%` Solution :Here, T= 2.5 SECOND, `DeltaT= (1)/(2)` second Therefore, the permissible error in the measurement of time period is `(DeltaT)/(T)xx 100= ((1)/(2))/(2.5)xx100= 20%`