# A classical mechanics problem by Pratik Shastri

**Classical Mechanics**Level 4

A pendulum oscillates, immersed in water. The mass of the bob is \(250 \ g\), length of the string is \(30 \ cm\), the radius of the bob is \(2 \ cm\) and density of water \(\rho_w\) is \(1000 \ kg/m^3\).

Calculate the time period of its oscillations (in seconds), considering its amplitude to be small.

\(\textbf{Assumptions}\)

\(\bullet\) Take \(g=9.8 \ m/s^2\)

\(\bullet\) Ignore drag forces.