Question

a pendulum has time period T in air. when it made to oscillate in water, it aquerida time period T=√2T. the density of the pendulum Bob is equal to​

Answer 1

a pendulum has time period T in air. when it made to oscillate in water, it aquerida time period T=√2T. the density of the pendulum Bob is equal to​

Explanation:

The effective acceleration of the bob in water =g=g[1−σρ] where a and ρ are the densities of water and the bob . The periods of oscillation of the bob in air and water are given as      

T=2πlg√ and T=2πlg√

∴  T/T=√g/g=g(1−σρ)g⎷  

             =1−σρ

√=1−1ρ√

Putting           T/T=1/√2

We get,      12=1−1ρ ⇒        

                      ρ=2