A particle executes SHM of amplitude A. The distance from the mean position when its's kinetic energy becomes equal to its potential energy is :
Solution
The total energy of a particle executing simple harmonic motion (SHM) is given by:
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$E = \frac{1}{2}m\omega^2A^2$
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where $m$ is the mass of the particle, $\omega$ is the angular frequency of the SHM, and $A$ is the amplitude of the motion.
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At any point during SHM, the kinetic energy of the particle is given by:
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$K = \frac{1}{2}m\omega^2(x^2 + A^2\cos^2\omega t)$
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where $x$ is the displacement of the particle from the mean position.
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The potential energy of the particle at the same point is given by:
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$U = \frac{1}{2}m\omega^2(x^2 + A^2\sin^2\omega t)$
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When the kinetic energy becomes equal to the potential energy, we have:
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$K = U$
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$$\frac{1}{2}m\omega^2(x^2 + A^2\cos^2\omega t) = \frac{1}{2}m\omega^2(x^2 + A^2\sin^2\omega t)$$
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Simplifying this equation, we get:
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$x^2 = \frac{1}{2}A^2$
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$x = \pm\frac{1}{\sqrt{2}}A$
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Therefore, the distance from the mean position when the kinetic energy becomes equal to the potential energy is $\boxed{\frac{1}{\sqrt{2}}A}$
About this question
Subject: Physics · Chapter: Oscillations · Topic: Simple Harmonic Motion
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