A pendulum of length $2\,m$ lift at $P$. When it reaches $Q$, it losses $10\%$ of its total energy due to air resistance. The velocity at $Q$ is .... $m/sec$
Medium
Download our app for free and get startedPlay store
(a) If $v$ is velocity of pendulum at $Q$
and $10\%$ energy is lost while moving from $P$ to $Q$
Hence, by applying conservation of between $P$ and $Q$
$\frac{1}{2}m{v^2} = 0.9\,(mgh)$

==>${v^2} = 2 \times 0.9 \times 10 \times 2$

==> $v = 6\,m/sec$

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
    A particle executes simple harmonic motion along a straight line with an amplitude $A$. The potential energy is maximum when the displacement is
    View Solution
  • 2
    A $1 \,kg$ block attached to a spring vibrates with a frequency of $1\, Hz$ on a frictionless horizontal table. Two springs identical to the original spring are attached in parallel to an $8\, kg$ block placed on the same table. So, the frequency of vibration of the $8\, kg$ block is ..... $Hz$
    View Solution
  • 3
    A simple pendulum with iron bob has a time period $T$. The bob is now immersed in a non-viscous liquid and oscillated. If the density of liquid is $\frac{1}{12}$ th that of iron, then new time period will be
    View Solution
  • 4
    The total energy of a particle executing S.H.M. is proportional to
    View Solution
  • 5
    A particle performs $SHM$ on $x-$ axis with time period of $0.5\,sec,$ such that it's velocity is zero at $x = -3\,cm$ and at $x = 9\,cm$. It was located at $x = 0$ and moving in negative $'x'$ at $t = 0$. The equation of $SHM$ of the particle is
    View Solution
  • 6
    A block of mass $m$ attached to massless spring is performing oscillatory motion of amplitude $'A'$ on a frictionless horizontal plane. If half of the mass of the block breaks off when it is passing through its equilibrium point, the amplitude of oscillation for the remaining system become $fA.$ The value of $f$ is
    View Solution
  • 7
    A simple harmonic wave having an amplitude a and time period $T$ is represented by the equation $y = 5\sin \pi (t + 4)m.$ Then the value of amplitude $(a)$ in $(m)$ and time period $(T) $ in second are
    View Solution
  • 8
    If particle is executing simple harmonic motion with time period $T$, then the time period of its total mechanical energy is ...........
    View Solution
  • 9
    An assembly of identical spring-mass systems is placed on a smooth horizontal surface as shown. At this instant, the springs are relaxed. The left mass is displaced to the/left and theiright mass is displaced to the right by same distance and released. The resulting collision is elastic. The time period of the oscillations of system is
    View Solution
  • 10
    A particle executes $S.H.M.$ and its position varies with time as $x=A$ sin $\omega t$. Its average speed during its motion from mean position to mid-point of mean and extreme position is
    View Solution