A second pendulum is shifted from a plane where `g = 9.8 m//s^(2)` to another place where `g = 9.82 m//s^(2)`. To keep period of oscillation constant its length should be

Options

A. decreased by `(2)/(pi^(2))`cm
B. increased by `(2)/(pi^(2))`cm
C. increased by `(2)/(pi)` cm
D. decreased by `(2)/(pi)` cm

Answer

B

Explanation

`T = 2pi sqrt((l)/(g)) rArr T^(2) = 4 pi^(2) (l)/(g)`
`Delta l = (1)/(pi^(2)) Delta g (T^(2) = 4)`