A simple pendulum is executing simple harmonic motion with a time period $T$. If the length of the pendulum is increased by $21\%$, the percentage increase in the time period of the pendulum of increased length is ..... $\%$
AIEEE 2003,AIIMS 2001, Medium
Download our app for free and get startedPlay store
(a) If initial length ${l_1} = 100$ then ${l_2} = 121$

By using $T = 2\pi \sqrt {\frac{l}{g}} $

$\Rightarrow \frac{{{T_1}}}{{{T_2}}} = \sqrt {\frac{{{l_1}}}{{{l_2}}}} $

Hence, $\frac{{{T_1}}}{{{T_2}}} = \sqrt {\frac{{100}}{{121}}} $

$\Rightarrow {T_2} = 1.1\,{T_1}$

$\%$ increase = $\frac{{{T_2} - {T_1}}}{{{T_1}}} \times 100 = 10\,\% $

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 diagram shows two oscillations. What is the phase difference between the oscillations?
    View Solution
  • 2
    For a simple pendulum the graph between $L$ and $T$ will be.
    View Solution
  • 3
    A particle is executing the motion $x = A\cos (\omega \,t - \theta )$. The maximum velocity of the particle is
    View Solution
  • 4
    The function $sin^2\,(\omega t)$ represents
    View Solution
  • 5
    A light balloon filled with helium of density $\rho_{ He }$ is tied to a long light string of length $l$ and the string is attached to the ground. If the balloon is displaced slightly in the horizontal direction from the equilibrium and released. Then,
    View Solution
  • 6
    A spring mass system executes damped harmonic oscillations given by the equation 

    $y = A{e^{ - \frac{{bt}}{{2m}}}}\sin (\omega 't + \phi )$

    where the symbols have their usual meanings. If a $2\ kg$ mass $(m)$ is attached to a spring of force constant $(K)$ $1250\ N/m$ , the period of the oscillation is $\left( {\pi /12} \right)s$ . The damping constant $‘b’$ has the value. ..... $kg/s$

    View Solution
  • 7
    Which of the following quantities are always negative in a $SHM$
    View Solution
  • 8
    Two particles are performing simple harmonic motion in a straight line about the same equilibrium point. The amplitude and time period for both particles are same and equal to $A$ and $T,$  respectively. At time $t=0$ one particle has displacement $A$ while the other one has displacement $\frac {-A}{2}$ and they are moving towards each other. If they cross each other at time $t,$ then $t$ is
    View Solution
  • 9
    A flat horizontal board moves up and down in $SHM$ of amplitude $\alpha$. Then the shortest permissible time period of the vibration such that an object placed on the board may not lose contact with the board is
    View Solution
  • 10
    When the potential energy of a particle executing simple harmonic motion is one-fourth of its maximum value during the oscillation, the displacement of the particle from the equilibrium position in terms of its amplitude $a$ is
    View Solution