A cylindrical plastic bottle of negligible mass of filled with $310\, ml$ of water and left floating in a pond with still water. If pressed downward slightly and released, it starts performing simple harmonic motion at angular frequency $\omega $. If the radius of the bottle is $2.5\, cm$ then $\omega $ is close to ..... $rad\, s^{-1}$  (density of water $= 10^3\, kg/m^3$)
JEE MAIN 2019, Diffcult
Download our app for free and get startedPlay store
$A\rho gx = {F_{restoring}}$

$\pi {r^2}\rho gx = n{\omega ^2}x$

$\therefore \omega \sqrt {\frac{{\pi {r^2}\rho g}}{{\rho v}}} $

$ = r\sqrt {\frac{{\pi g}}{v}}  = 2.5 \times {10^{ - 2}}\sqrt {\frac{{3.14 \times 10}}{{310 \times {{10}^{ - 6}}}}} $

$ = 2.5 \times {10^{ - 2}} \times {10^2}\sqrt {10} $

$\omega  = 2.5 \times \sqrt {10} $

$\therefore f = \frac{{2.5 \times \sqrt {10} }}{{2\pi }} = 1.25$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    The displacement time graph of a particle executing $S.H.M.$ is given in figure: (sketch is schematic and not to scale) Which of the following statements is are true for this motion?

    $(A)$ The force is zero $t=\frac{3 T}{4}$

    $(B)$ The acceleration is maximum at $t=T$

    $(C)$ The speed is maximum at $t =\frac{ T }{4}$

    $(D)$ The $P.E.$ is equal to $K.E.$ of the oscillation at $t=\frac{T}{2}$

    View Solution
  • 2
    When a mass $m$ is attached to a spring, it normally extends by $0.2\, m$. The mass $m$ is given a slight addition extension and released, then its time period will be
    View Solution
  • 3
    Two masses $M_{A}$ and $M_{B}$ are hung from two strings of length $l_{A}$ and $l_{B}$ respectively. They are executing SHM with frequency relation $f_{A}=2 f_{B}$, then relation
    View Solution
  • 4
    A particle performs $SHM$ about $x = 0$ such that at $t = 0$ it is at $x = 0$ and moving towards positive extreme. The time taken by it to go from $x = 0$ to $x = \frac{A}{2}$ is ..... times the time taken to go from $x = \frac{A}{2}$ to $A$. The most suitable option for the blank space is
    View Solution
  • 5
    The amplitude of a simple pendulum, oscillating in air with a small spherical bob, decreases from $10\, cm$ to $8\, cm$ in $40\, seconds$ . Assuming that Stokes law is valid, and ratio of the coefficient of viscosity of air to that of carbon dioxide is $1.3$ . The time in which amplitude of this pendulum will reduce from $10\, cm$ to $5\, cm$ in carbon dioxide will be close to ..... $s$ $(ln\, 5 = 1.601,ln\, 2 = 0 .693)$
    View Solution
  • 6
    The amplitude and the periodic time of a $S.H.M.$ are $ 5\,cm$ and $6\,sec$ respectively. At a distance of $2.5\,cm$ away from the mean position, the phase will be
    View Solution
  • 7
    Two springs with spring constants ${K_1} = 1500\,N/m$ and ${K_2} = 3000\,N/m$ are stretched by the same force. The ratio of potential energy stored in spring will be
    View Solution
  • 8
    A particle is excuting a simple harmonic motion. Its maximum acceleration is $\alpha $ and maximum velocity is $\beta $. Then its frequency of vibration will be
    View Solution
  • 9
    Two small bodies of mass of $2\, kg$ each attached to each other using a thread of length $10\, cm$, hang on a spring whose force constant is $200\, N/m$, as shown in the figure. We burn the thread. What is the distance between the two bodies when the top body first arrives at its highest position .... $cm$ ? (Take $\pi^2 = 10$)
    View Solution
  • 10
    The angular amplitude of a simple pendulum is $\theta_0$. The maximum tension in its string will be
    View Solution