A second pendulum is shifted from Delhi to London . If the accelereation due to gravity at london is 981cm/s^(2) and increases in length of the pendulum is observed to be 0.2 cm , then the acceleration due to gravity at Delhi is

A second pendulum is shifted from Delhi to London . If the accelereati

1.	A second pendulum is shifted from Delhi to London . If the accelereation due to gravity at london is 981cm/s^(2) and increases in length of the pendulum is observed to be 0.2 cm , then the acceleration due to gravity at Delhi is
Answer» `983cm/s^(2)` `979cm/s^(2)` `985cm/s^(2)` `977cm//s^(2)` Solution :Time period of pendulum is GIVEN by `t = 2pisqrt((l)/(G))` `RARR l = (gT^(2))/(4pi^(2))` For second.s pendulum, T =2 s `therefore l = (g(2^(2)))/(4pi^(2)) = (g)/(pi^(2))` At London, `therefore l = (g)/(pi^(2)) = (981)/(10) = 98.1` cm `(pi^(2) = 9.8696 ~~ 10)` At Delhi, `therefore l = 0 .2 = (g.)/(pi^(2)) = (g.)/(10)` `rArr g. - 10L - 2 = 10 xx 98.1 - 2 = 979 cm//s^(2)`