Correct Answer - B
The time period of a simple pendulum is
`T=2pisqrt((L)/(g))`
where L is length of the pendulum
or `L=(gT^(2))/(4pi^(2))` . . . (i)
the time period of the simple pendulum which ticks seconds is 2 s.
`thereforeT=2s`
Substitution in (i), we get
`L=((9.8ms^(-2))(2s)^(2))/(4xx(3.14)^(2))=1m`