Derivation of Impulse and Momentum

Thread starter IncognitoSOS
Start date Oct 27, 2009
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Derivation Impulse Momentum

AI Thread Summary

The discussion focuses on deriving the kinetic energy formula in terms of momentum, specifically showing that KE = p^2/2m. The initial equation for kinetic energy is given as KE = 1/2MV^2, and momentum is defined as p = mv. Participants suggest rewriting velocity in terms of momentum to facilitate the derivation. The key step involves substituting v with p/m, leading to the desired equation. The conversation emphasizes the relationship between kinetic energy and momentum in classical mechanics.

Oct 27, 2009

IncognitoSOS

Show that the kinetic energy of an object can be written in terms of the momentum as
KE = p^2/2m.

Homework Equations

KE = 1/2MV^2

The Attempt at a Solution

To be honest, I don't know where to even start with this problem. It equals PV/2 but I still need to find a way to derive p^2/2m

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Oct 27, 2009

Doc Al

Mentor

What's the definition of p?

Oct 27, 2009

IncognitoSOS

p=mv

Oct 28, 2009

Doc Al

Mentor

IncognitoSOS said:

p=mv

Now write v in terms of p and make use of it.

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