The amplitude of a damped oscillator decreases to $0.9\,times$ its original magnitude in $5\,s.$ In another $10\,s$ it will decrease to $\alpha $ times its original magnitude, where $\alpha $ equals
Medium
Download our app for free and get started
$A=A_{0} e^{-h t}$
$0.9 A_{0}=A_{0} e^{-k t}$
$-k t=\ln (0.9) \Rightarrow-15 k=3 \ln (0.9)$
$A=A_{0} e^{-15 k}=A_{0} e^{-\ln (0.9)^{3}}$
$=(0.9)^{3} A_{0}=0.729 A_{0}$
Hence,
option $(C)$ is correct answer.
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.*
You are holding a shallow circular container of radius $R$, filled with water to a height $h ( h < < R )$. When yon walk with speed $v$, it is seen that water starts spilling over. This happens due to the resonance of the periodic impulse given to the container (due to walking) with the oscillation of the water in the container. If the time period of water oscillating in the container is inversely proportional to $\sqrt{ h }$, then $v$ is proportional to
The equation of motion of a particle of mass $1\,g$ is $\frac{{{d^2}x}}{{d{t^2}}} + {\pi ^2}x = 0$ where $x$ is displacement (in $m$ ) from mean position. The frequency of oscillation is .... $s$ (in $Hz$ )
A particle doing simple harmonic motion, amplitude $= 4\, cm$, time period $= 12\, sec$. The ratio between time taken by it in going from its mean position to $2 \,cm$ and from $2\, cm$ to extreme position is
Two particles $P$ and $Q$ start from origin and execute Simple Harmonic Motion along $X-$axis with same amplitude but with periods $3$ seconds and $6$ seconds respectively. The ratio of the velocities of $ P$ and $Q$ when they meet is