Why is kinetic energy equal to half of momentum squared over mass?

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Kinetic energy is derived from the relationship between momentum and mass, expressed as KE = P^2 / 2m. The discussion highlights that kinetic energy can also be represented as KE = 1/2 mv^2, linking it to momentum (p) through the equation p = mv. By substituting momentum into the kinetic energy formula, it can be shown that KE is equal to half of momentum squared divided by mass. The integration of mv dv is mentioned as a method to derive kinetic energy. This mathematical relationship underscores the connection between kinetic energy and momentum in classical mechanics.
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I know that :

kinetic energy of something = P^2 / 2m , or momentum squared over 2m


why so?

I see that taking the integral of mv dv = kenitic.

can you prove this to
 
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You know p in terms of m and v. You also know E in terms of m and v. This should get you started.
 
KE = \frac{1}{2} mv ^ 2

= \frac{1}{2} pv

= \frac{1}{2} \frac{pmv}{m}

= \frac{1}{2} \frac{p ^ 2}{m}
 
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