A simple pendulum has time period 2s in air. If the whole arrangement is placed in a non viscous liquid whose density is `1//2` times the density of bob, find the time period of oscillation in liquid.

Explanation

`2=2pisqrt(l//g)` …(i)
when bob is immersed in liquid, then effective acceleration due to gravity,
`f^(')=(((4)/(3)pir^(3)rho-(4)/(3)pir^(3)rho^('))g)/((4)/(3)pir^(3)rho)`
`=((rho-rho^('))/(rho))g=((rho-rho//2)/(rho))g=(g)/(2)`
`T^(')=2pisqrt((l)/(g//2))=sqrt(2)T=sqrt(2)xx2=2sqrt(2)s`