[tex](adsbygoogle = window.adsbygoogle || []).push({});

v_f^2-v_0^2=2ax

[/tex]

Multiplying by m,

[tex]

\frac{mv_f^2-mv_i^2}{2}=max

[/tex]

[tex]

\frac{1}{2}mv_f^2-\frac{1}{2}mv_i^2=Fx

[/tex]

This equation is true for all of the motions which include a force. Thereforewecall the left side KE difference, and the right side work done.

Is energy a thing which can only be defined mathematically? Or are there any other ways to define it? If yes, why did Euler call itvis viva? Was it only because of KE? If no, what leads us to conclude that there is a thing called energy?

For almost every physical definition, we have an imagination, a perception, a conception, something inexplicable. Where is this coming from? When we were babies, playing with Legos (K'Nex for me) we learn about dynamics and perhaps energy. I've read that smells, tastes and views were perceived the same by a little baby. Perhaps we develop that conciousness at that age.

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# There is a thing called energy?

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