Three students $S_{1}, S_{2}$ and $S_{3}$ perform an experiment for determining the acceleration due to gravity $(g)$ using a simple pendulum. They use different lengths of pendulum and record time for different number of oscillations. The observations are as shown in the table.

Student No. Length of pendulum $(cm)$ No. of oscillations $(n)$ Total time for oscillations Time period $(s)$
$1.$ $64.0$ $8$ $128.0$ $16.0$
$2.$ $64.0$ $4$ $64.0$ $16.0$
$3.$ $20.0$ $4$ $36.0$ $9.0$

(Least count of length $=0.1 \,{m}$, least count for time $=0.1\, {s}$ )

If $E_{1}, E_{2}$ and $E_{3}$ are the percentage errors in $'g'$ for students $1,2$ and $3$ respectively, then the minimum percentage error is obtained by student no. ....... .

  • [JEE MAIN 2021]
  • A

    $4$

  • B

    $3$

  • C

    $1$

  • D

    same in all

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  • [JEE MAIN 2022]

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