Undergrad How can we prove the kinetic energy equation

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SUMMARY

The discussion focuses on proving the kinetic energy equation, specifically the derivation of the formula KE = 1/2 mv². It establishes that the work done (W) in a mechanical system is equal to the change in kinetic energy, represented mathematically as W = ∫F.ds. The proof utilizes the relationship between force, acceleration, and displacement, leading to the conclusion that when velocity components are aligned, the kinetic energy can be expressed as the sum of individual contributions from each component, confirming the standard equation.

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TL;DR
does the kinetic energy equation always work? it has proved for only when acceleration and and velocity are in the same direction.
Proof of kinetic energy
work done equals a change in kinetic energy in a mechanical system.
δW = F.ds
W = ∫F.ds
W = m∫a.ds
W = m∫(dv/dt).ds
W = m∫v.dv

here if v and dv are in the same direction the change in kinetic energy will be the usual equation. what happens if both are in different directions how can we prove that the general equation for kinetic energy will be 1/2mv^2?
 
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It works individually on each component’s contribution. That is ##\int v_1 dv_1 = v_1^2/2## etc.
 
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Likes john1954, B0B, sophiecentaur and 1 other person
Thank you. I forgot to think that.
 

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