A second's pendulum on the earth is taken to the moon, where acceleration due to gravity is nearly 1/6 th that on the earth. If it is to act as second's pendulum there too on the moon, its length should be

Options

A. decreased by 17%
B. increased by 17%
C. decreased by 83%
D. increased by 600%

Answer

C

Explanation

`(l_(2)-l_(1))/(l_(1))xx100=(g_(2)-g_(1))/(g_(1))xx100`
`=(g//6-g)/(g)xx100`
`=(-5)/(6)xx100=-83.3`