Energy changes in mass spring system

AI Thread Summary
The discussion focuses on the relationship between kinetic energy and velocity in a mass-spring system, specifically questioning why the kinetic energy versus time curve mirrors the modulus of the velocity time curve. It outlines a mathematical approach to prove this by considering the general trajectory of a harmonic oscillator, expressed as x(t)=Acos(ωt)+Bsin(ωt). The next step involves differentiating this equation to derive the velocity function v(t). Finally, the kinetic energy K(t) is calculated using the formula K(t)=1/2 mv(t)^2. This analysis aims to clarify the connection between kinetic energy and velocity in harmonic motion.
Asad Raza
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Why is the kinetic energy vs time curve of a mass spring system is just a modulus of respective velocity time curve.
How can we prove it mathematically ?
 
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Actually that's not true!
Step1) Consider the most general trajectory for a harmonic oscillator:## x(t)=A\cos \omega t+B\sin\omega t ##
Step2) Differentiate it w.r.t. time to get the velocity ##v(t)##.
Step3) Put ##v(t)## in ##K(t)=\frac 1 2 m v(t)^2 ##.
 
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