In an oscillating spring mass system, a spring is connected to a box filled with sand. As the box os

Question

In an oscillating spring mass system, a spring is connected to a box filled with sand. As the box oscillates, sand leaks slowly out of the box vertically so that the average frequency $\omega(t)$ and average amplitude $A(t)$ of the system change with time $t$. Which one of the following options schematically depicts these changes correctly?

Professor PC Thomas Classes · Answer

(d) : As the box oscillates, sand leaks slowly out of the box which leads to decrease in effective mass of the bob. As, frequency is inversely proportional to the square root of $m$, hence average frequency ( $\omega$ ) increases and amplitude will decrease due to dissipation of energy.