A body of mass $1~\text{kg$ is attached to the lower end of a vertically suspended spring of force constant $600~\text{N/m}$. If another body of mass $0.5~\text{kg}$ moving vertically upward hits the suspended body with a velocity $3~\text{m/s}$ and is embedded in it, then the frequency of the oscillation is}
Show Hint
For spring oscillations after mass attachment, use $f = \dfrac{1}{2\pi} \sqrt{\dfrac{k}{m}}$ with the total mass.